Glossary

Amor asteroid

The Amor asteroids   are a group of near-Earth asteroids (NEAs) named after the asteroid 1221 Amor. They have orbital semi-major axes a > 1 AU and perihelium distance 1.0167 < q < 1.3 AU. They approach the orbit of the Earth from beyond, but do not cross it. Most Amors do cross the orbit of Mars. It is estimated that 32% of the total number of NEAs are Amors.

Apollo asteroid

The Apollo   asteroids are a group of near-Earth asteroids named after asteroid 1862 Apollo. They are Earth-crosser asteroids that have orbital semi-major axes greater than that of the Earth (a > 1 AU) and a perihelion distance q < 1.0167 AU. It is estimated that 62% of the total number of NEAs are Apollos.

Aten asteroid

The Aten asteroids   are a group of near-Earth asteroids, named after asteroid 2062 Aten. They have orbital semi-major axes a of less than 1 AU and aphelion distances Q > 0.9833. It is estimated that 6% of the total number of NEAs are Atens.

IEO asteroids have a < 1 AU and Q < 0.983 AU and so never cross Earth's orbit.

Main-belt asteroid

The asteroid belt   is the region of the Solar System located roughly between the orbits   of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets. The asteroid belt   region is also termed the main belt to distinguish it from other   concentrations of minor planets within the Solar System.

MOID

Minimum Orbit Intersection Distance (see   Introduction)

NEA

Near Earth Asteroid (see Introduction)

NEO

Near Earth Object (asteroid, comet)

PHA

Potentially Hazardous Asteroid (see Introduction)

Units

6.37103 × 10³ km = mean radius of the Earth

1 Lunar Distance (LD)

3.84401 × 10⁵ km = 0.00257 AU = 60.34 R_Earth, the mean distance   from the Earth to the Moon

1.495979 × 10⁸ km = 389.17 LD, the mean distance   from the Earth to the Sun

H magnitude

V-band magnitude an asteroid would have at 1 AU distance from the Earth, viewed at opposition

1801, Jan 1

First and largest asteroid discovered, 1 Ceres (H = 3.34 mag, D = 952 km, main-belt asteroid), by Giuseppe Piazzi (1746 – 1826, Italy) at the Osservatorio Astronomico di Palermo. Asteroid Cerere Ferdinandea was named in honour of King Ferdinand IV of Sicily, and later became known  simply as Ceres. Carl Gauss developed the math to determine an accurate orbit for Ceres and published his results in November 1801. Given the definition of planets and dwarf planets accepted by the IAU XXVI General Assembly in 2006, Ceres is considered a dwarf planet rather than an asteroid. See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1+Ceres&orb=1>.
Ref: 
- G. Piazzi, 1802, Della scoperta del nuovo planeta Cerere Ferdinandea (Palermo: Nella Stamperia Reale).
See also: <en.wikipedia.org/wiki/Ceres_(dwarf_planet)>, <www.space.com/12969-giant-asteroid-ceres-telescopes-skywatching.html>.

L'Aigle Meteorite. In the early afternoon of 26 April 1803 a meteorite shower of more than 3000 fragments fell upon the town of L'Aigle (Normandy, France). See: <en.wikipedia.org/wiki/L'Aigle_(meteorite)>.

Weston Meteorite. At 6:30 on the morning of 14 December 1807, a blazing fireball about two-thirds the size of the Moon was seen traveling southwards by early risers in Vermont and Massachusetts (USA). Three loud explosions were heard over the town of Weston in Fairfield County, Connecticut. Stone fragments fell in at least 6 places. See: <peabody.yale.edu/collections/meteorites-and-planetary-science/weston-meteorite>, <en.wikipedia.org/wiki/Weston_meteorite>.

Uden Meteorite (Netherlands). A 600 g meteorite was found. See: <www.dwc.knaw.nl/DL/publications/PU00015500.pdf>, <www.sterrenkunde.nl/index/encyclopedie/meteoren.html>.

Blauwkapel Meteorite (Netherlands). Two pieces were found, of 2.7 and 7 kg. See: <www.dwc.knaw.nl/DL/publications/PU00015500.pdf>, <www.sterrenkunde.nl/index/encyclopedie/meteoren.html>.

New York City Fireball and Airburst (USA). See: <www.meteoritehistory.info/AJS/S2VIEWS/V30P186.HTM>, <http://en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

The Meteor Procession of 20 July 1860, visible from the Great Lakes to New York State (USA), continuing out over the Atlantic Ocean.
Ref:
-      Walt Whitman, 1859-1860, in Leaves of Grass, "Year of Meteors.";
-      A.G. Pope, 5-1-2010, Astronomical dating of Edvard Munch's summer sky paintings, University Honors Program, Texas State University;
- R. Sinnott, 2010, Sky & Telescope, 7 June 2010, "Walt Whitman's "Meteor-Procession"."
See: <www.skyandtelescope.com/community/skyblog/newsblog/95765719.html>.
-      D.W. Olson, R.L Doescher, M.S. Olson, A.G. Pope,  2010, Sky & Telescope, 120, No.1, July 2010, p. 28, "Walt Whitman's "Year of Meteors"."
See: <www.skyandtelescope.com/community/skyblog/newsblog/95765719.html>, <philosophyofscienceportal.blogspot.com/2010/06/walt-whitman-wrote-about-strange-huge.html>, <www.txstate.edu/news/news_releases/news_archive/2010/06/YearOfMeteors060110.html>, <www.newscientist.com/gallery/whitman-mystery-solved/3>, <www.newscientist.com/blogs/culturelab/2010/06/the-forensic-astronomer-donald-olson.html>, <cosmiclog.msnbc.msn.com/_news/2010/06/02/4448882-150-year-old-meteor-mystery-solved>, <apod.nasa.gov/apod/ap100722.html>, <en.wikipedia.org/wiki/Earth-grazing_fireball>.

1864, May 14

Orgueil Meteorite rain over Orgueil (Southern France). Some 20 stones fell over an area of several square kilometres, with a total weight of 14 kg.
Ref:
-      M. Gounelle, P. Spurný, P.A. Bland, 2006, Meteoritics & Planetary Science, 41, 135, "The orbit and atmospheric trajectory of the Orgueil meteorite from historical records."
See : <www.springerlink.com/content/m470723364612j6x/>.
See also:  <en.wikipedia.org/wiki/Orgueil_(meteorite)>.

1868, July 11

Asteroid 100 Hekate (H = 7.67 mag, D = 88.7 km, main-belt asteroid) discovered by James C. Watson (1838 – 1880) at Ann Arbor (MI, USA). 100^th numbered asteroid in the data base of the IAU Minor Planet Center at Cincinnati Observatory (Ohio, USA).  See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=100+Hekate+&orb=1>, <en.wikipedia.org/wiki/100_Hekate>.

Forest City Meteorite Fall, Forest City (Iowa, USA),  2 May 1890.
Ref:
-      H.H. Nininger, 1942, Popular Astronomy, 50, 111, "A celestial bomb."
See also: <en.wikipedia.org/wiki/Meteorite_falls>.

1891,  Dec 22

First photographic discovery of an asteroid, 323 Brucia (H = 9.73 mag, D = 35.8 km), by Maximilian F.J.C. Wolf (1863 – 1932) at the Landessternwarte Heidelberg-Königstuhl (Heidelberg, Germany).  See: <en.wikipedia.org/wiki/323_Brucia>.

1893

G.K. Gilbert (1893) suggested impacts as most likely process for forming lunar craters.
Ref:
-      G.K. Gilbert, 1893, Bulletin of the Philosophical Society of Washington, 12, 241, "The Moon’s face: A study of the origin of its features." See: <adsabs.harvard.edu/abs/1893QB591.G46......>.

1898, Aug 13

First discovery of a NEA: asteroid 433 Eros (1898 DQ, H = 11.16 mag, D = 34.4 × 11.2 × 11.2 km, orbital P = 1.76 yr, Amor asteroid), by Carl Gustav Witt (1866 – 1948) at the Urania Sternwarte Berlin (Germany), and independently by Auguste Charlois (1864 – 1910) at the Observatoire de Nice (France). Second-largest NEA known. Its perihelion distance of 1.133 AU brings it with 0.15 AU of the orbit of the Earth.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1898+DQ&orb=1>, <en.wikipedia.org/wiki/433_Eros>.
Ref:
- P. Michel, P. Farinella, Ch. Froeschlé, 1996, Nature, 380, 689, "The orbital evolution of the asteroid Eros and implications for collision with the Earth." See: <adsabs.harvard.edu/abs/1996Natur.380..689M>.
See also: <www.oaa.gr.jp/~oaacs/mp/BriefHistoryofMPCbyConradBardwell.pdf>.

Helsinki Fireball and Airburst (Finland). See: <www.somerikko.net/collection/meteorites.php?id=374>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

1 NEA known. See: <neo.jpl.nasa.gov/stats/>.

Asteroid 2010 KV39 (H = 26.8 mag, D ≈ 15 m) passed Earth at a nominal miss distance of 4.7 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+KV39&orb=1>.
See also: 26 May 2010.

Asteroid 99942 Apophis (2004 MN4, H = 19.7 mag, D ≈ = 325 ± 15 m, M ≈ 4.7 × 10¹⁰ kg, orbital P = 0.89 yr, PHA) passed Earth at a nominal miss distance of 10.97 LD. Minimum miss distance 10.90 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004+MN4&orb=1>, <www.esa.int/Our_Activities/Space_Science/Herschel_intercepts_asteroid_Apophis>, <en.wikipedia.org/wiki/99942_Apophis>.
See also: 13 April 2029.

Asteroid 2010 XC15 (H = 21.4 mag, D ≈ 200 m, PHA) passed Earth at a nominal miss distance of 2.9 LD. Minimum miss distance 0.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+XC15&orb=1>.
See also: 27 December 2022.

1908, Jun 30

Tunguska event, Siberia, Russia. According to Boslough & Crawford (2008), possibly an asteroid with D ≈ 30 – 50 m, exploding in an airburst with E ≈ 4 megaton TNT at an altitude of ~8.5 km, flattening ~2000 km² of forest.
Ref:
- L.A. Kulik, 1938, Astronomical Society of the Pacific Leaflets, Vol. 3, No. 109, p. 78, "The meteorite of June 30, 1908, in Central Siberia." See: <adsabs.harvard.edu/abs/1938ASPL....3...78K>;
- L'. Kresak, 1978, Bulletin Astronomical Institutes of Czechoslovakia, 29, 129, "The Tunguska object – a fragment of Comet Encke?"; See: <adsabs.harvard.edu/abs/1978BAICz..29..129K>; 
-  R.P. Turco, O.B. Toon, C. Park, et al., 1981, Science,  214, 19, "Tunguska meteor fall of 1908 – effects on stratospheric ozone." See: <adsabs.harvard.edu/abs/1981Sci...214...19T>;
-  Z. Sekanina, 1983, Astronomical Journal, 88, 1382, "The Tunguska event – no cometary signature in evidence." Erratum, 1984, Astronomical Journal, 89, 185. See: <adsabs.harvard.edu/abs/1983AJ.....88.1382S>, <adsabs.harvard.edu/abs/1984AJ.....89..185S>;
-  C.F. Chyba, 1993, Astronomy, 21, no.12, p.38, "Death from the sky." See: <adsabs.harvard.edu/abs/1993Ast....21R..38C>; 
-  C.F. Chyba, P.J. Thomas, K.J. Zahnle, 1993, Nature, 361, 40, "The 1908 Tunguska explosion: atmospheric disruption of a stony asteroid." See: <adsabs.harvard.edu/abs/1993Natur.361...40C>;
-  R.A. Gallant, 1994, Sky & Telescope, 87, no. 6, p. 38, "Journey to Tunguska"." See: <adsabs.harvard.edu/abs/1994S%26T....87...38G>;
-  P. Farinella, L. Foschini, Ch. Froeschlé, 2001, Astronomy & Astrophysics, 377, 1081, "Probable asteroidal origin of the Tunguska cosmic body." See: <adsabs.harvard.edu/abs/2001A%26A...377.1081F>;
- K. Zahnle, 1996, Nature, 383, 674, "Tunguska: leaving no stone unburned." See: <www.nature.com/nature/journal/v383/n6602/pdf/383674a0.pdf>;
- G. Longo, 2007, in: P. Bobrowsky & H. Rickman (eds.), 2007, Comet/Asteroid Impacts and Human Society (Berlin: Springer), p. 304, "The Tunguska event." See: <adsabs.harvard.edu/abs/2007caih.book.....B>;
-  D.I. Steel, 2008, Nature, 453, 1157, "Tunguska at 100." See: <www.nature.com/news/2008/080625/full/4531157a.html>;
-  M.B.E. Boslough, D.A. Crawford, 2008, Intern. J. of Impact Engineering, 35, 1441, "Low-altitude airbursts and the impact threat." See: <www.sciencedirect.com/science/article/pii/S0734743X08001784>, <www.sandia.gov/ldrd/images/Posters/Boslough_Poster.pdf>; 
-  B. Napier, D. Asher, 2009, Astronomy & Geophysics, 50, 1.18, "The Tunguska impact event and beyond." See: <www.sciencedirect.com/science/article/pii/S0734743X08001784>;
-  V. Rubtsov, 10 March 2013, e-print arXiv, 1302.6273, "Reconstruction of the Tunguska Event of 1908: neither an asteroid, nor a comet core." See: <adsabs.harvard.edu/abs/2013arXiv1302.6273R>.
See also: <impact.arc.nasa.gov/news_detail.cfm?ID=179>, <www.time.com/time/photogallery/0,29307,1818757,00.html>, <apod.nasa.gov/apod/ap111002.html>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>, <en.wikipedia.org/wiki/Tunguska_event>.

1 NEA known. See: <neo.jpl.nasa.gov/stats/>.

Minor planet astronomy became organized in a formal way at  the Rechen-Institut in Berlin-Dahlem (Germany),  director Fritz Cohn (1878 – 1940).
Ref:
- G. Stracke, 1935, Astronomische Nachrichten, 255, 189,  "25 Jahre genäherte Bearbeitung der Bahnen der Kleinen Planeten im  Astronomischen Rechen-Institut." Predecessor of the MPC.   See: <adsabs.harvard.edu/abs/1935AN....255..189S>.   
See also: 1947.

1910, May 9

Asteroid 2007 JB21 (H = 25.4 mag, D ≈ 30 m) passed Earth at a nominal miss distance of 0.9 LD. Minimum miss distance 0.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2007+JB21&orb=1>.
See also: 8 May 2054.

The Nakhla Meteorite fell to Earth on 28 June 1911 in the Nakhla region of Abu Hommos (Alexandria, Egypt). Many people witnessed its explosion in the upper atmosphere before the meteorite fell to Earth in an area of 4.5 km in diameter. About forty pieces were recovered. Recovered fragments ranged in weight from 20 to 1813 g. See: <en.wikipedia.org/wiki/Nakhla_meteorite>.

Asteroid 719 Albert (1911 MT = 2000 JW8, H = 15.8 mag, D ≈ 2.5 km) passed Earth at 80 LD.
Discovered by Johann Palisa (1848 – 1925), discoverer of 122 asteroids at the Vienna Observatory (Austria). Lost (the last missing), but rediscovered 1 May 2000 by Jeffrey A. Larsen with the Spacewatch Telescope in Arizona (USA).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1911+MT&orb=1>, <en.wikipedia.org/wiki/719_Albert>.
See also: <www.space.com/scienceastronomy/asteroid_found_000510.html>,  <en.wikipedia.org/wiki/Johann_Palisa>.

1913, Feb 9 

Earth-grazing fireball. A meteor procession observed from Canada to Bermuda and beyond.
Ref:
-    J.A. O'Keefe, 1959, Journal Royal Astronomical Society of Canada, 53, 59, "A probable natural satellite: the meteor procession of February 9, 1913." As of  2008, four Earth-grazing fireballs have been scientifically observed: on 10 August 1972, 13 October 1990, 29 March 2006, and 7 August 2007. See: <adsabs.harvard.edu/abs/1959JRASC..53...59O>, <en.wikipedia.org/wiki/Earth-grazing_fireball>.

1914, Dec 31

Asteroid 152680 (1998 KJ9, H = 19.4 mag, D ≈ 500 m, PHA) passed Earth at a nominal miss distance of 0.6 LD. Minimum miss distance 0.6 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1998+KJ9&orb=1>, <en.wikipedia.org/wiki/(152680)_1998_KJ9>.

Asteroid 2010 RF12 (H = 28.4 mag, D ≈ 8 m) passed Earth at a nominal miss distance of 1.2 LD. Minimum miss distance 1.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+RF12&orb=1>, <en.wikipedia.org/wiki/2010_RF12>.
See also: 8 September 2010, 6 September 2095.

Asteroid 2012 KT42 (H = 28.8 mag, D ≈ 6 m) passed Earth at a nominal miss distance of 5.0 LD. Minimum miss distance 0.5 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+KT42&orb=1>.
See also: 4 December 1954, 29 May 2012.

Asteroid 2012 DA14 (H = 24.1 mag, D ≈ 40 × 20 m), discovered in 2012 by the Spanish Observatorio Astronomico de la Sagra, passed Earth at a nominal miss distance of 1.13 LD. Minimum miss distance 1.13 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+DA14&orb=1>.
See also: 16 February 2012 and 15 February 2013.

Asteroid 2002 GQ (H = 26.4 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 0.9 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002+GQ&orb=1>.

Michigan - Indiana Fireball and Airburst (USA). See: <chroniclingamerica.loc.gov/lccn/sn84026749/1919-11-27/ed-1/seq-1/>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

3 NEAs known, of which 0 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

1921

Alfred Wegener (1880 – 1930, Germany), 1921, Die Entstehung der Mondkrater (Braunschweig: Friedrich Vieweg & Sohn). Translation: A. Wegener, 1975, The Moon, 4, 211, "The origin of lunar craters." See: <adsabs.harvard.edu/abs/1975Moon...14..211W>.

Asteroid 2012 DY13 (H = 28.0 mag, D ≈ 9 m) passed Earth at a nominal miss distance of 6.7 LD. Minimum miss distance 0.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+DY13&orb=1>.
See also: 20 February 2012.

1923

Discovery of asteroid 1923 NZ, (H = 9.6 mag, D = 47.8 km, main-belt asteroid), by Karl W. Reinmuth (1892 – 1979) at the Landessternwarte Heidelberg-Königstuhl in Heidelberg (Germany). On his proposal, the IAU named the asteroid 1000 Piazzia, being the 1000th documented asteroid, in honour of Giuseppe Piazzi who discovered asteroid Ceres in 1801.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1923+NZ&orb=1>, <en.wikipedia.org/wiki/1000_Piazzia>.
Ref:
-  B. Asplind, 1926, Astronomische Nachrichten, 228, 89, "Benennung der Planeten 1000 – 1002." See: <adsabs.harvard.edu/abs/1926AN....228...89A>.

1924, Sep 27

Asteroid 2003 SR84 (H = 25.9 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 0.9 LD. Minimum miss distance 0.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003+SR84+&orb=1>.

Discovery of near-Earth asteroid 1036 Ganymed (1924 TD, H = 9.45, D = 31.66 km, orbital P = 4.34 yr), by W.H. Walter Baade at Hamburg-Bergedorf Observatory (Germany). Largest known NEA. In 1998, Arecibo radar images revealed a near spherical object.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1924+TD&orb=1>, <en.wikipedia.org/wiki/1036_Ganymed>.
Ref:
- G. Hahn, P. Magnusson, A.W. Harris, et al., 1989, Icarus, 78, 363, "Physical studies of Apollo-Amor asteroids - UBVRI photometry of 1036 Ganymed and 1627 Ivar." See: <adsabs.harvard.edu/abs/1989Icar...78..363H>;
- P. Michel, R. Gonczi, P. Farinella, Ch. Froeschlé, 1999, Astronomy & Astrophysics, 347, 711, "Dynamical evolution of 1036 Ganymed, the largest near-Earth asteroid." See: <adsabs.harvard.edu/abs/1999A%26A...347..711M>;
- S.K. Fieber-Beyer, M.J. Gaffey, P.A. Abell, 2011, Icarus, 212, 149, "Mineralogical characterization of Near Earth Asteroid (1036) Ganymed. See  <adsabs.harvard.edu/abs/2011Icar..212..149F>.

Ellemeet Meteorite. Whit aloud noise, so that horses and cows took fright, this meteorite fell down in a meadow near Ellemeet, on the island of Schouwen (the Netherlands) on 28 August 1925, about 11:30 hr a.m. See: <www.dwc.knaw.nl/DL/publications/PU00015500.pdf>, <www.sterrenkunde.nl/index/encyclopedie/meteoren.html>.

1925, Aug 30

Asteroid 163132 (2002 CU11, H = 18.3 mag, D ≈ 800 m, PHA) passed Earth at a nominal miss distance of 0.9 LD. Minimum miss distance 0.9 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002+CU11&orb=1>.

Asteroid 2005 UW5 (H = 27.5 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 8.6 LD. Minimum miss distance 0.03 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2005+UW5&orb=1>.
See also: 30 October 2005, 29 October 2076.

Asteroid 2002 JE9 (H = 21.3 mag, D ≈ 200 m, PHA) psed Earth at a nominal miss diasstance of 8.8 LD. Minimum miss distance 0.2 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002+JE9&orb=1>.
See also: 11 April 1971.

5 NEAs known, of which 0 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

Asteroid 2011 AX22 (H = 24.7 mag, D ≈ 40 m) passed Earth at a nominal miss distance of 3.4 LD. Minimum miss distance 0.2 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+AX22&orb=1>.
See also: 13 May 2055.

1930, Aug 13

Curuçá Fireball and Airburst over Rio Curuçá (Amazonas, Brazil). Coinciding with the annual Perseid meteor shower. See: <www.uh.edu/engines/epi1102.htm>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.
Ref:
- N. Vasilyev, G. Andreev, 1989, WGN, the Journal of the International Meteor Organization, 17, 245, "The Brazilian twin of the Tunguska Meteorite: myth or reality?" See: <adsabs.harvard.edu/abs/1989JIMO...17..245V>; 
- M.E. Bailey, D.J. Markham, S. Massai, J.E. Scriven, 1995, The Observatory, 115, 250, "The 1930 August 'Brazilian Tunguska' Event." See: <adsabs.harvard.edu/abs/1995Obs...115..250B>;
- D. Steel, 1995, WGN, the Journal of the International Meteor Organization, 23, 207, "Two 'Tunguskas' in South America in the 1930's?" See: <adsabs.harvard.edu/abs/1995JIMO...23..207S>;
- W. Napier, D. Asher, 2009, Astronomy & Geophysics, 50, 1.18, "The Tunguska impact event and beyond." See: <onlinelibrary.wiley.com/doi/10.1111/j.1468-4004.2009.50118.x/abstract>;
- G. Cordero, A. Poveda, 2011, Planetary and Space Science, 59(1), 10, "Curuça 1930: A probable mini-Tunguska?" See: <adsabs.harvard.edu/abs/2011P%26SS...59...10C>.

Asteroid 2008 JP24 (H = 26.7 mag, D ≈ 15 m) passed Earth at a nominal miss distance of 2.2 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008+JP24&orb=1>.

Asteroid 2010 RX30 (H = 27.2 mag, D ≈ 15 m) passed Earth at a nominal miss distance of 2.8 LD. Minimum miss distance 1.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+RX30&orb=1>, <en.wikipedia.org/wiki/2010_RX30>
See also: 8 September 2010.

1932, Apr 24

First discovery of an Earth-orbit crossing NEA: asteroid 1862 Apollo (1932 HA, H = 16.25 mag, D ≈ 1.7 km, PHA), by Karl W. Reinmuth (1892 – 1979) at the Landessternwarte Heidelberg-Königstuhl (Heidelberg, Germany); lost; recovered in 1973.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1932+HA&orb=1>, <en.wikipedia.org/wiki/1862_Apollo>.
Ref:
-  M. Davidson, 1932, Monthly Notices Roy. Astron. Soc., 92, 691, "The Reinmuth object." See: <adsabs.harvard.edu/abs/1932MNRAS..92..691D>;
- L.A. Lebofsky, G.J. Veeder, G.H. Rieke, et al., 1981, Icarus, 48, 335, "The albedo and diameter of 1862 Apollo." See: <adsabs.harvard.edu/abs/1981Icar...48..335L>.

Asteroid 2012 CU (H = 26.0 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 1.2 LD. Minimum miss distance 0.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+CU&orb=1>.

In December 1932, scientists surveying the southern Egyptian desert came upon pieces of a translucent, pale yellow-green, glassy substance, from tiny fragments to football-sized chunks, scattered over a huge area at the Libyan border. Known as Libyan desert glass, this almost pure silica contained isotopes showing it to be of extraterrestrial origin.  Further reading: see 3 March 2006.
See: <www.sciencemag.org/cgi/content/summary/311/5765/1223c>,  <en.wikipedia.org/wiki/Libyan_desert_glass>.

Arroyomolinos de León Fireball and Airburst (Spain). See:
<www.lpi.usra.edu/meetings/lpsc2011/pdf/1368.pdf>,  <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

Discovery of asteroid 1934 CT and promptly lost. Re-discovered  4 January 1989 and listed as 1989 AC = 4179 Toutatis.
See: 4 January 1989,
<ssd.jpl.nasa.gov/sbdb.cgi?sstr=1934+CT+&orb=1>,  <en.wikipedia.org/wiki/4179_Toutatis>.

Asteroid 2011 JV10 (H = 29.7 mag, D ≈ 4 m) passed Earth at a nominal miss distance of 4.1 LD. Minimum miss distance 0.3 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+JV10&orb=1>.
See also: 5 May 2011.

Asteroid 2011 EL11 (H = 19.9 mag, D ≈ 350 m, PHA) passed Earth at a nominal miss distance of 9.0 LD. Minimum miss distance 0.9 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+EL11&orb=1>.

G. Stracke, 1935, Astronomische  Nachrichten, 255, 189, "25 Jahre genäherte Bearbeitung der Bahnen der  Kleinen Planeten im Astronomischen Rechen-Institut." Predecessor of the MPC. At the time 1301 minor planets were numbered.  See:  <adsabs.harvard.edu/abs/1935AN....255..189S>.

Rupununi Fireball and Airburst over Rupununi (British Guyana), near the date of the peak of the annual Geminid meteor shower.
Ref:
-  D. Steel, 1995, WGN, the Journal of the International Meteor Organization, 23, 207, "Two 'Tunguskas' in South America in the 1930's?" See: <adsabs.harvard.edu/abs/1995JIMO...23..207S>;
- W. Napier, D. Asher, 2009, Astronomy & Geophysics, 50, 1.18, "The Tunguska impact event and beyond." See: <onlinelibrary.wiley.com/doi/10.1111/j.1468-4004.2009.50118.x/abstract>.

F. Watson, 1936, Popular Astronomy, 44, 2, "Meteor craters." See: <adsabs.harvard.edu/abs/1936PA.....44....2W>.

F. Watson, E.M. Cook, 1936, Popular Astronomy, 44, 131, "The detonating Fireball of May 26, 1935." See: <adsabs.harvard.edu/abs/1936PA.....44..131W>.

Asteroid 2010 VB1 (H = 23.3 mag, D ≈ 80 m) passed Earth at a nominal miss distance of 0.5 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+VB1+&orb=1>.
See also: 7 January 2086.

1936, Feb 12

Second discovery of an Earth-orbit crossing NEA: asteroid 2101 Adonis (1936 CA, H = 18.7 mag, D ≈ 0.5 – 1.2 km, PHA), by Eugene Delporte (1872 – 1955, Belgium); lost; recovered in 1977.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1936+CA&orb=1>, <en.wikipedia.org/wiki/2101_Adonis>.

Asteroid 2008 EZ84 (H = 26.1 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 3.8 LD. Minimum miss distance > 0.02 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008+EZ84&orb=1>.

F.G. Watson, H. Shapley, 1937, Annals of the Astronomical Observatory of Harvard College, 105, no. 32, The Observatory, p. 623.  See: <adsabs.harvard.edu/abs/1937AnHar.105..623W>.

1937, Oct 30

Asteroid 69230 Hermes (1937 UB, H = 17.5 mag, D ≈ 800 m, PHA) passed Earth at 1.9 LD. Discovered by Karl W. Reinmuth (1892 – 1979) at the Landessternwarte Heidelberg-Königstuhl (Heidelberg, Germany); lost; recovered 15 October 2003. Arecibo radar observations on the same day revealed it to be a binary asteroid, with components of D ≈ 400 m, separated by 1200 m.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1937+UB&orb=1>, <en.wikipedia.org/wiki/69230_Hermes>.
See also: <science.nasa.gov/headlines/y2003/31oct_hermes.htm>, <www.news.cornell.edu/releases/Oct03/Arecibo.asteroid.deb.html>,
<adsabs.harvard.edu/abs/2003IAUC.8227....2M>.

Asteroid 2012 DW60 (H = 26.5 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 2.6 LD. Minimum miss distance 0.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+DW60&orb=1>.

Chicora meteoroid. A meteoroid exploded as it entered the atmosphere above Chicora (PA, USA) on June 24, 1938. Based on the size of the explosion, the rock's initial mass (before it broke up) may have been more than 450 tons. However, only scant pieces of the meteorite were ever found — located miles away from where the main mass, missing to this day, is thought to have landed. Several reports on the Chicora meteorite mention that an unsuspecting cow was struck and injured by one falling shard; other accounts say that the poor animal was killed. See: <www.lifeslittlemysteries.com/1535-when-space-attacks-6-craziest-meteor-impacts-history.html>, <en.wikipedia.org/wiki/Chicora,_Pennsylvania#Chicora_Meteor>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

Asteroid 2012 KP24 (H = 26.4 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 4.3 LD. Minimum miss distance 0.6 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+KP24&orb=1>.
See also: 28 May 2012.

9 NEAs known, of which 3 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

F. Watson, 1940, Journal of the Royal Astronomical Society of Canada, 34, 418, "The meteor of May 7, 1928." See: <adsabs.harvard.edu/abs/1940JRASC..34..418W>.

Asteroid 2000 AG6 (H = 25.3 mag, D ≈ 30 m) passed Earth at a nominal miss distance of 9.2 LD. Minimum miss distance 0.7 LD.
See: <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

Chelyabinsk Airburst and Fireball (Russia).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+UK10&orb=1>.

Asteroid 2011 UK10 (H = 24.9 mag, D ≈ 40 m) passed Earth at a nominal miss distance of 1.7 LD. Minimum miss distance 0.3 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+UK10&orb=1>.

Asteroid 2006 BA (H = 27.6 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 1.4 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2006+BA&orb=1>.

H.H. Nininger, 1942, Popular Astronomy, 50, 111, "A celestial bomb." On the Forest City (Iowa, USA) fall of 2 May 1890.  See: <adsabs.harvard.edu/abs/1942PA.....50..111N>.

Asteroid 69230 Hermes (1937 UB, H = 17.5 mag, D ≈ 800 m, PHA) passed Earth at a nominal miss distance of 1.7 LD. Minimum miss distance 1.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1937+UB&orb=1>, <en.wikipedia.org/wiki/69230_Hermes>.

Antoine de Saint Exupéry, 1943, Le Petit Prince, (Paris: Editions Gallimard). Featuring: fictional asteroid B612. See: <en.wikipedia.org/wiki/The_Little_Prince>.
See also: <www.universetoday.com/96509/chasing-the-little-prince-in-new-york-city/>.

Asteroid 2007 VF189 (H = 28.3 mag, D ≈ 8 m) passed Earth at a nominal miss distance of 5.7 LD. Minimum miss distance 0.9 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2007+VF189&orb=1>.
See also: 14 November 2007, 13 November 2080.

Daytime Fireball over Bulannyo (Rhodesia). Norman Appleton witnessed a meteor so bright he remembered it his entire life. Right before his eyes a tremendous smoking fireball streaked across the daytime sky. Years later, as an accomplished member of the Guild of Aviation Artists, he recorded his memories in a painting.  See: <apod.nasa.gov/apod/ap010728.html>, <www.gava.org.uk/index.cfm?page=searchresults&searchType=quickSearch>.

Asteroid 2008 LH2 (H = 24.4 mag, D ≈ 50 m) passed Earth at a nominal miss distance of 8.2 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008+LH2&orb=1>.

1947

IAU Minor Planet Center (MPC), established by the International Astronomical Union, Commission 20, and succeeding the work which was carried out since 1910 by the Rechen-Institut in Berlin-Dahlem (Germany), started operations at the Observatory of the University of Cincinnati (Ohio, USA), director Paul Herget (1908 – 1981, USA). At the time, 1564 minor planets were numbered. Upon Herget's retirement in 1978, the amount of numbered minor planets had reached 2060, and the MPC moved to the Harvard-Smithsonian Center for Astrophysics, Cambridge (MA, USA) with Brian G. Marsden (1937 – 2010) as director. For a history of the MPC, see:
-  B.G. Marsden, 2009, IAU Information Bulletin, No. 104, p. 67, "History of the Minor Planet Center." See: <www.cfa.harvard.edu/iau/mpc.html>, <www.iau.org/static/publications/IB104.pdf>, p. 67.

1947, Feb 12

Sikhote-Alin Fireball and Airburst passed over Sikhote-Alin mountains (Primorye, Russia), creating a 32 km long smoke trail in the sky at an altitude of 5.6 km. The bright flash and the deafening sound of the fall were observed at 300 km around the point of impact not far from Luchegorsk and ~440 km northeast of Vladivostok. The pre-impact mass of the meteoroid may have been 100,000 kg. The strewn field of this meteorite covered an elliptical area of about 1.3 km. Some fragments made craters, the largest of which was about 26 m across and 6 m deep.
Ref:
-  R.A. Gallant, 1997, Sky & Telescope, 93, no. 2, p.50, "Sikhote-Alin: 50 years later." See: <adsabs.harvard.edu/abs/1997S%26T....93b..50G>.
See also: <meteoritemag.uark.edu/604.htm>, <www.lifeslittlemysteries.com/1535-when-space-attacks-6-craziest-meteor-impacts-history.html>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>, <en.wikipedia.org/wiki/Sikhote-Alin_meteorite>.

Asteroid 2008 GM2 (H = 28.4 mag, D ≈ 8 m) passed Earth at a nominal miss distance of 1.3 LD. Minimum miss distance 0.6 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008+GM2&orb=1>.
See also: 3 April 2008.

The international yearbook "Ephemerides of minor planets", published since 1948 for the International Astronomical Union by the Institute of Applied Astronomy in St Petersburg (Russian Federation), contains information on orbital elements of numbered minor planets and the circumstances of their observations during the best observation periods. See: <www.ipa.nw.ru/PAGE/DEPFUND/LSBSS/engephem.htm>

Asteroid 2008 WG96 (H = 26.3 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 6.1 LD. Minimum miss distance 0.07 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008+WG96&orb=1>.

1949

Ralph E. Baldwin (…. – 19.., USA), The Face of the Moon (Chicago: UCP), describing the damage that a NEO impact might cause on Earth.
Reviews: <adsabs.harvard.edu/abs/1949PA.....57..257B>.

1949, Jan 1

Asteroid 2003 YS70 (H = 28.8 mag, D ≈ 6 m) passed Earth at a nominal miss distance of 0.7 LD. Minimum miss distance 0.6 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003+YS70+&orb=1>.

Asteroid 99942 Apophis (2004 MN4, H = 19.7 mag, D ≈ = 325 ± 15 m, M ≈ 4.7 × 10¹⁰ kg, orbital P = 0.89 yr, PHA) passed Earth at a nominal miss distance of 10.87 LD. Minimum miss distance 10.87 LD.
See: : <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004+MN4&orb=1>, <www.esa.int/Our_Activities/Space_Science/Herschel_intercepts_asteroid_Apophis>, <en.wikipedia.org/wiki/99942_Apophis>, See: 13 April 2029.

1949, Jun 27

Discovery of Earth-orbit crossing asteroid 1566 Icarus (1949 MA, H = 16.9 mag, D = 1.0 km, Apollo asteroid, also Venus- and Mercury-orbit crossing, PHA) by Walter Baade (1893 – 1960, Germany/USA). In 1968 Icarus became the first minor planet to be observed by radar. It is plausible that Icarus and asteroid 5786 Talos (1991 RC, H = 17.0 mag, D ≈ 1.3 km) and asteroid 2007 MK6, H = 19.9 mag, D ≈ 350 m) are related.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1949+MA&orb=1>, <en.wikipedia.org/wiki/1566_Icarus>.
Ref:
-  D.K. Yeomans, 1991, Astronomical Journal, 101, 1920, "A comet among the near-earth asteroids?" [Erratum, 1992, AJ, 104, 1266].  See: <adsabs.harvard.edu/abs/1991AJ....101.1920Y>, <adsabs.harvard.edu/abs/1992AJ....104.1266Y>;
- D. Steel, 1991, Nature, 354, 265, "Our asteroid-pelted planet." See: <adsabs.harvard.edu/abs/1991Natur.354..265S>;
- K. Ohtsuka, H. Arakida, T. Ito, et al., 2007, Astrophysical Journal Letters, 668, L71, "Apollo asteroids 1566 Icarus and 2007 MK6: Icarus family members?" See: <adsabs.harvard.edu/abs/2007ApJ...668L..71O>.

Asteroid 2010 XR69 (H = 25.4 mag, D ≈ 30 m) passed Earth at a nominal miss distance of 4.8 LD. Minimum miss distance 0.9 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+XR69&orb=1>.

13 NEAs known, of which 5 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

The Yerkes-McDonald Survey of asteroids (1950 – 1952), down to v = 16.5, was performed  by astronomers Gerard P. Kuiper (1905 – 1973, Netherlands/USA), George A. Van Biesbroeck (1880 – 1974, Belgium/USA), Cornelis J. van Houten (1920 – 2002, Netherlands), Ingrid M. van Houten-Groeneveld (Netherlands) and Tom Gehrels (Netherlands/USA). A number of 3247 objects were found.
Ref:
-  G.P. Kuiper, Y. Fujita, T. Gehrels, I. M. Groeneveld, J. Kent, G.A. Van Biesbroeck, C.J. van Houten, 1958, Astrophysical Journal Supplement, 3, 289, "Survey of asteroids".  See: <adsabs.harvard.edu/abs/1958ApJS....3..289K>.

Ernst Julius Öpik (1893-1985, Estonia – Ireland), 1951, Proc. Royal Irish Academy, 54A, 165, "Collision probabilities with the planets and the distribution of interplanetary matter." Discussing the possible importance of the Yarkovsky effect discovered by Ivan Osipovich Yarkovsky (1844-1902, Russian-Polish  civil engineer) for meteoroids moving about the solar system.  See: <adsabs.harvard.edu/abs/1951PRIA...54..165O>, <en.wikipedia.org/wiki/Yarkovsky_effect>.

Asteroid 2004 VM24 (H = 25.7 mag, D ≈ 25 m) passed Earth at a nominal miss distance of 2.6 LD. Minimum miss distance 0.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004+VM24&orb=1>.

V.V. Radzievskii, 1952, Astron. Zh., 29, 162, "A mechanism for the disintegration of asteroids and meteorites".  See: <adsabs.harvard.edu/abs/1952AZh....29..162R>.

E.J. Öpik, 1952, Irish Astronomical Journal, 2, 95, "Collisions with heavenly bodies." See: <adsabs.harvard.edu/abs/1952IrAJ....2...95O>.

Asteroid 2004 VZ (H = 24.5 mag, D ≈ 45 m) passed Earth at a nominal miss distance of 4.0 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004+VZ&orb=1>.

A.C.B. Lovell, 1954, Meteor Astronomy (Oxford: Clarendon Press).  See: <adsabs.harvard.edu/abs/1954QB741.L6.......>. A critical review of this book, with comments on meteor velocities in particular, is given by E.J. Öpik, 1955, Irish Astronomical Journal, 3, 144, "Meteor astronomy." See: <adsabs.harvard.edu/abs/1955IrAJ....3..144O>.

1954,  Nov 30

Hodges meteorite. First known modern case of a human hit by a space rock occurred in Sylacauga (Alabama, USA). A 4 kg stone chondrite crashed through a roof and hit Mrs. Ann Hodges in her living room after it bounced off her radio. She was badly bruised. The Hodges meteorite, or Sylacauga meteorite, is on exhibit at the Alabama Museum of Natural History.  See: <www.lifeslittlemysteries.com/1535-when-space-attacks-6-craziest-meteor-impacts-history.html>, <en.wikipedia.org/wiki/Sylacauga_(meteorite)>.

G.P. Kuiper, 1954, Proceedings of the National Academy of Sciences of the United States of America, 40(12), 1096, "On the origin of the lunar surface features." See: <adsabs.harvard.edu/abs/1954PNAS...40.1096K>.

Asteroid 2012 KT42 (H = 28.8 mag, D ≈ 6 m) passed Earth at a nominal miss distance of 5.9 LD. Minimum miss distance 0.03 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+KT42&orb=1>.
See also: 3 December 1915, 29 May 2012.

Asteroid 2006 RJ1 (H = 22.2 mag, D ≈ 140 m) passed Earth at a nominal miss distance of 1.5 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2006+RJ1&orb=1>.

1956, Jan

M.W. De Laubenfels (1956) suggested the idea that the dinosaurs demise is due to an impact event and the resulting super-hot winds that would result. He scaled up the effects of the Tunguska blast and made first suggestion of the death of the dinosaurs being impact related. Mammals first appeared in Cretaceous with the most outstanding type differing little from the modern opossum. The author argues for a brief period of extreme heat enough to kill exposed large animals. Birds, mammals, aquatic animals would have survived. He notes in Oct 1937 close Earth approach of Hermes and Tunguska event. He computes amount of heat available from a 100 m sized impactor at 10 km/s and notes that if kinetic energy turned into heat, it would be enough to boil 10¹⁶ tons of water whereas entire oceans are 10¹⁸ tons.
Ref:
-  M.W. De Laubenfels (Oregon State College), 1956,  Journal of Paleontology, 30, 207, "Dinosaur extinction: one more hypothesis." See: <www.norwebster.com/astrohit/>.

C.S. Beals, G.M. Ferguson, A. Landau, 1956, Sky & Telescope, 15, 296, "The Holleford Crater in Ontario." See: <adsabs.harvard.edu/abs/1956S%26T....15..296B>.

Harold C. Urey (1893 – 1981, USA), 1956, Astrophysical Journal, 124, 623, "Diamonds, meteorites, and the origin of the Solar System." See: <adsabs.harvard.edu/abs/1956ApJ...124..623U>.

C.S. Beals, 1957, Sky & Telescope, 16, 526, "A probable meteorite crater of great age." See: <adsabs.harvard.edu/abs/1957S%26T....16..526B>.

Asteroid 2010 XW58 (H = 24.8 mag, D ≈ 37 m) passed Earth at a nominal miss distance of 0.1584 LD. Minimum miss distance 0.1568 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+XW58&orb=1>.

E.J. Öpik, 1958, Physics of meteor flight in the atmosphere (New York: Interscience Publishers).  See: <adsabs.harvard.edu/abs/1958QB741.O38......>.

C.S. Beals, 1958, Nature, 181, 559, "A survey of terrestrial craters." See: <adsabs.harvard.edu/abs/1958Natur.181..559B>.

E.J. Öpik, 1958,  Irish Astronomical Journal, 5, 34, "On the catastrophic effect of collisions with celestial bodies." Öpik proposed that NEO impacts might have handicapped the development of land in the paleontological history.  See: <adsabs.harvard.edu/abs/1958QB741.O38......>.

G.P. Kuiper, Y. Fujita, T. Gehrels, I. M. Groeneveld, J. Kent, G.A. Van Biesbroeck, C.J. van Houten, 1958, Astrophysical Journal Supplement, 3, 289, "Survey of asteroids".  See: <adsabs.harvard.edu/abs/1958ApJS....3..289K>.

Asteroid 2008 TZ (H = 25.4 mag, D ≈ 30 m) passed Earth at a nominal miss distance of 2.7 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008+TZ&orb=1>.

Asteroid 2012 BX34 (H = 27.6 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 0.6 LD. Minimum miss distance 0.5 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+BX34+&orb=1>.
See also: 27 January 2012.

Příbram Meteorite Fall, the first meteorite simultaneously observed by several stations in the Czech Republic. The network was initiated locally at  Ondřejov Observatory. By 1963, the network consisted of 5 stations. In 1968 it had expanded by the installation of about 15 new stations in Germany, and was named the European Fireball Network.
Ref:
-  P. Spurný, J. Borovička, L. Shrbený, 2007, in: A. Milani, G.B. Valsecchi & D. Vokrouhlický (eds.), Proc. IAU Symposium No. 236 on Near Earth Objects, our Celestial Neighbors: Opportunity and Risk, Prague (Czech Republic), 14-18 August 2006 (Cambridge: CUP), p. 121, "Automation of the Czech part of the European Fireball Network: equipment, methods and first results." See: <adsabs.harvard.edu/abs/2007IAUS..236..121S>, <www.dlr.de/pf/en/desktopdefault.aspx/tabid-623/1043_read-26813/>, <en.wikipedia.org/wiki/European_Fireball_Network>.

20 NEAs known, of which 8 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

Asteroid 2001 BA16 (H = 25.8 mag, D ≈ 25 m) passed Earth at a nominal miss distance of 3.7 LD. Minimum miss distance 0.06 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001+BA16&orb=1>.
See also: 15 January 2001.

Tom Gehrels took Palomar Schmidt (1.2-m) plates on which C.J. van Houten et al. (1970) discovered over 2000 asteroids with v < 20 mag, including four NEAs.
Ref:
-  C.J. van Houten, I. van Houten-Groeneveld, P. Herget & T. Gehrels, 1970, Astronomy & Astrophysics Suppl., 2, 339, "The Palomar-Leiden survey of faint minor planets." See: <adsabs.harvard.edu/abs/1970A%26AS....2..339V>;
- C.J. van Houten, P. Herget, B.G. Marsden, 1984, Icarus, 59, 1, "The Palomar-Leiden survey of faint minor planets – Conclusion." See: <adsabs.harvard.edu/abs/1984Icar...59....1V>.

Asteroid 2004 UH1 (H = 28.2 mag, D ≈ 8 m) passed Earth at a nominal miss distance of 0.4 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004+UH1+&orb=1>.
See also: 22 April 1968, 24 October 2004.

1961, Oct 

Eugene M. Shoemaker and Edward C.T. Chao proved the (24 km diameter) Nördlingen Ries crater (Nördlingen, western Bavaria, Germany), formed ~14.4 My ago in the Miocene, to be caused by meteorite impact. Another impact crater, the much smaller (3.8 km diameter) Steinheim crater, is located ~ 42 km WSW from the centre of Ries. The two craters are believed to have formed nearly simultaneously by the impact of a binary asteroid. The impactors probably had diameters of ~ 1.5 km (Ries) and 150 m (Steinheim), and a pre-impact separation of some tens of kilometers.
Ref:
-  E.M. Shoemaker, E.C.T. Chao, 1961, Journal of Geophysical Research, 66, 3371, "New evidence for the impact origin of the Ries Basin, Bavaria, Germany." See: <adsabs.harvard.edu/abs/1961JGR....66.3371S>.
See also: <en.wikipedia.org/wiki/N%C3%B6rdlinger_Ries>, <www.unb.ca/passc/ImpactDatabase/images/ries.htm>, <www.lpi.usra.edu/meetings/nordlingen2010/>, <www.hq.nasa.gov/alsj/a14/a14ries.html>.
The Earth Impact Database lists some 170 known impact craters on Earth.  See: <www.unb.ca/passc/ImpactDatabase/>.

H.C. Urey, 1962, Nature, 193, 1119, " Life-forms in meteorites: origin of life-like forms in carbonaceous chondrites. Introduction." See: <adsabs.harvard.edu/abs/1962Natur.193.1119U>.

1963

Eugene M. Shoemaker (1928 – 1997, USA) and colleagues firmly established the impact origin of the Meteor Crater in Arizona. Meteor Crater is located approximately 69 km east of Flagstaff, near Winslow in the northern Arizona desert of the United States. The site was formerly known as the Canyon Diablo Crater. Scientists generally refer to it as Barringer Crater, in honor of the geologist Daniel Barringer (1860 – 1929) who was first to suggest that it was produced by meteorite impact. Barringer Meteor Crater lies at an elevation of about 1,740 m (5,709 ft) above sea level. It is ~ 1,200 m in diameter, 170 m deep, and is surrounded by a rim that rises 45 m above the surrounding plains. The center of the crater is filled with 210–240 m of rubble lying above crater bedrock. The incoming asteroid had a diameter of ~ 25 m and a velocity of 15 km/s. The largest meteorite found is the so-called Holsinger meteorite, weighing 639 kg, on display in the Meteor Crater Visitor Center on the rim of the crater.
See: <en.wikipedia.org/wiki/Meteor_Crater>, <en.wikipedia.org/wiki/Barringer_Crater>, <en.wikipedia.org/wiki/Holsinger_Meteorite>.
Ref:
-   E.M. Shoemaker, 1963, in: B.M. Middlehurst & G.P. Kuiper (eds.), The Moon, Meteorites, and Comets (Chicago: UCP), p. 301, "Impact mechanics at Meteor Crater, Arizona." See: <adsabs.harvard.edu/abs/1963mmc..book..301S>.
- D.J. Roddy, E.M. Shoemaker, 1995, Meteoritics 30(5), 567, "Meteor Crater (Barringer Meteorite Crater), Arizona: summary of impact conditions." See: <adsabs.harvard.edu/abs/1995Metic..30Q.567R>.
- M. Boslough, 1996, Skeptical Inquirer, Vol. 20.2, March/April 1996, "Scientific knowledge is money in the bank." See: <www.csicop.org/si/show/scientific_knowledge_is_money_in_the_bank>.
- D.A. Kring, 1997, Meteoritics& Planetary Science, 32, 517, "Air blast produced by the Meteor Crater impact event and a reconstruction of the affected environment." See: <adsabs.harvard.edu/abs/1997M%26PS...32..517K>.
- D.A. Kring, 1999, Sky & Telescope, 98(5), 48, "Calamity at Meteor Crater." See: <adsabs.harvard.edu/abs/1999S%26T....98e..48K>.
- H.J. Melosh, G.S. Collins, 2005, Nature, 434, 157, "Meteor Crater formed by a low-velocity impact." See: <adsabs.harvard.edu/abs/2005Natur.434..157M>;
See also: <www.unb.ca/passc/ImpactDatabase/images/barringer.htm>, <antwrp.gsfc.nasa.gov/apod/ap070623.html>.

1963

Initiation of the European Fireball Network.
Ref:
-  J. Olberst, S. Molau, D. Heinlein, et al., 1998, Meteoritics & Planetary Science, 33, 49, "The 'European Fireball Network': Current status and future prospects". See: <adsabs.harvard.edu/abs/1998M&PS...33...49O>.
See also: <www.molau.de/meteore/imc97-2.html>, <adsabs.harvard.edu/abs/2007IAUS..236..121S>, <www.nature.com/nature/journal/v423/n6936/full/423123a.html>, <www.dlr.de/pf/en/desktopdefault.aspx/tabid-623/1043_read-1425/>.

Initiation of the Prairie Fireball Network, with a prototype station in Havanna (IL, USA). By May 1964, 16 stations were operational.
Ref:
-  R.E. McCrosky, H. Boeschenstein, 1965, SAO Special Report, No. 173, "The Prairie Fireball Network." See: <adsabs.harvard.edu/abs/1965SAOSR.173.....M >;
- Z. Ceplecha, R.E. McCrosky, 1997, Meteoritics & Planetary Science, 32, A157, "Prairie Network fireballs: data on height, distance and brightness for each measured time-mark." See: <adsabs.harvard.edu/abs/1997M%26PSA..32..157C>.

M.R. Dence, M.J.S. Innes, C.S. Beals, 1963, Astronomical Journal, 68, 534, "On the probable meteorite origin of the Clearwater Lakes, Quebec." See: <adsabs.harvard.edu/abs/1963AJ.....68..534D>.

R. L. C. Gallant, 1963, Nature, 200, 414, "Changes in the Earth's axis due to large meteorite collisions." See: <adsabs.harvard.edu/abs/1963Natur.200..414G>.

C.S. Beals, M.R. Dence, A.J. Cohen, 1964, Astronomical Journal, 69, 134, "Evidence suggesting a meteorite impact origin for Lac Couture, Quebec." See: <adsabs.harvard.edu/abs/1964AJ.....69R.134B>.

Dandridge M. Cole, Donald W. Cox, 1964, Islands in space: the challenge of the planetoids (Philadephia: Chilton).  See: <discoveryenterprise.blogspot.com/2007/08/islands-in-space-challenge-of.html>.

René L.C. Gallant (1906 – 1985, Belgium), 1964, Bombarded Earth (London: John Baker Publishers Ltd).  See: <www.catastrophism.com/cdrom/pubs/books/gallant/index.htm>,  <www.velikovsky.info/Ren%C3%A9_Gallant#cite_note-palmer2003-0>.

Asteroid 2007 RS1 (H = 31.0 mag, D ≈ 3 m) passed Earth at a nominal miss distance of 8.4 LD. Minimum miss distance 0.5 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2007+RS1&orb=1>.
See also: 5 September 2007.

1965, Jan 17

Asteroid 2007 BD (H = 25.6 mag, D ≈ 30 m) passed Earth at a nominal miss distance of 1.0 LD. Minimum miss distance 0.9 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2007+BD+&orb=1>.
See also: 18 January 2007.

Revelstoke Fireball and Airburst, 64 km NW of the city of Revelstoke (BC, Canada): an extremely bright bolide giving off sparks was observed to travel for 100 km in 8 seconds.  See: <www.lpi.usra.edu/meteor/metbull.php?code=22592> <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

Asteroid 2011 DS (H = 27.0 mag, D ≈ 15 m) passed Earth at a nominal miss distance of 9.2 LD. Minimum miss distance 0.6 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+DS&orb=1>.
See also: 14 August 2047, 18 February 2050.

1966, July

In an UPI report, Australian scientist S.T. Butler noted an upcoming close Earth approach by the asteroid 1566 Icarus (1949 MA, H = 16.9 mag, D = 1.0 km, PHA) in 1968.  He suggested that the asteroid could possibly be destroyed by a nuclear warhead if it neared the Earth. Paul Sandorff (MIT, U.S.A.) then assigned a hypothetical problem to his system engineering class.  This “Icarus Project” drew a good deal of attention, including a Time Magazine story in June 1967 and a book the following year.
Ref:Time Magazine, 16 June 1967, "Systems engineering: avoiding an asteroid"; Louis A. Kleinman (ed.), 1968, "Project Icarus: an MIT student project in systems engineering" (Cambridge: MIT Press); MIT Students, 1979, "Project Icarus – revised edition" (Cambridge: MIT Press).  See: <en.wikipedia.org/wiki/Project_Icarus>.

Lake Huron, Michigan-Ontario Fireball and Airburst (USA, Canada). See: <adsabs.harvard.edu/full/1966JRASC..60..257H>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

Leonid Fireball over Table Mountain Observatory (Angeles National Forest, Wrightwood, CA, USA).  See: <apod.nasa.gov/apod/ap981113.html>.

Vilna Fireball and Airburst (Alberta, Canada). See: <adsabs.harvard.edu/full/1969JRASC..63...61F>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

The largest know meteorite, the Hoba meteorite, lies on the farm "Hoba West", not far from Grootfontein, in the Otjozondjupa Region of Namibia. It has been uncovered in 1920, but, because of its large mass, has never been moved from where it fell. The main mass is estimated at over 54,000 kg, and it is the largest known meteorite (as a single piece) and the most massive naturally-occurring piece of iron known at the Earth's surface. The Hoba meteorite is thought to have landed less than 80,000 years ago. It is inferred that the Earth's atmosphere slowed the object down to the point that it fell to the surface at terminal velocity, thereby remaining intact and causing little excavation. The Hoba meteorite is unusual in that it is flat on both major surfaces, possibly causing it to have skipped across the top of the atmosphere in the way a flat stone skips on water.  Size: 2.7 × 2.7 × 0.9 m.
Ref: 
- J.D. Fernie, 1967, Journal of the Royal Astronomical Society of Canada, 61, 127, "Journey via Otjiwarongo. A trip to the Hoba Meteorite. See: <adsabs.harvard.edu/abs/1967JRASC..61..127F>, <en.wikipedia.org/wiki/Hoba_meteorite>.

European Fireball Network established.
Ref:
-  P. Spurný, J. Borovička, L. Shrbený, 2007, in: A. Milani, G.B. Valsecchi & D. Vokrouhlický (eds.), Proc. IAU Symposium No. 236 on Near Earth Objects, our Celestial Neighbors: Opportunity and Risk, Prague (Czech Republic), 14-18 August 2006 (Cambridge: CUP), p. 121, "Automation of the Czech part of the European Fireball Network: equipment, methods and first results." See: <adsabs.harvard.edu/abs/2007IAUS..236..121S>, <www.dlr.de/pf/en/desktopdefault.aspx/tabid-623/1043_read-26813/>, <en.wikipedia.org/wiki/European_Fireball_Network>.

C.S. Beals, 1968, Contributions Dominion Observatory Ottawa, 4(29), 1, "Theories of the origin of Hudson Bay. I. On the possibility of a catastrophic origin for the great arc of eastern Hudson Bay." See: <adsabs.harvard.edu/abs/1968CoDAO...4....1B>.

G.W. Wetherill, J.G. Williams, 1968, Journal of Geophysical Research, 73, 635, "Evaluation of the Apollo asteroids as sources of stone meteorites." See: <adsabs.harvard.edu/abs/1968JGR....73..635W>.

Asteroid 2004 UH1 (H = 24.5 mag, D ≈ 45 m) passed Earth at a nominal miss distance of 1.0 LD. . Minimum miss distance 0.2 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004+UH1+&orb=1>.
See also: 24 October 1960, 24 October 2004.

Asteroid 2010 JR34 (H = 27.7 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 4.0 LD. Minimum miss distance 0.9 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+JR34&orb=1>.

1968, Jun 14

Asteroid 1566 Icarus (1949 MA, H = 16.9 mag, D = 1.0 km, PHA) passed Earth at 16.5 LD. Observed by radar by NASA's Goldstone Solar System Radar (CA, USA) and the MIT Haystack Observatory (Westfort, MA, USA).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1949+MA&orb=1>, <en.wikipedia.org/wiki/1566_Icarus>.
Ref:
-  R.M. Goldstein, 1968, Science, 162, 903, "Radar observations of Icarus." See: <adsabs.harvard.edu/abs/1968Sci...162..903G>.
- B.G. Marsden, 1998, Boston Sunday Globe, 29 March 1989, "How the asteroid story hit: an astronomer reveals how a discovery spun out of control." See: <www.minorplanetcenter.net/iau/pressinfo/1997XF11Globe.html>.

1969, Feb 8

Chihuahua Fireball, witnessed falling over the Mexican State of Chihuahua. After breaking up in the atmosphere, an extensive search for pieces was conducted; it is often described as "the best-studied meteorite in history." Some 2000 kg of meteorite material has been collected. The largest piece found, the Allende meteorite of 0.520 kg, is notable for possessing abundant, large calcium-aluminum-rich inclusions, which are among the oldest objects formed in the Solar System. The ²³⁸U/²³⁵U isotope ratio found in the Allende meteorite by Brennecka et al. (2010) implies that the Solar System is some 5 million years younger than thought previously.
See : <en.wikipedia.org/wiki/Allende_meteorite>.
Ref:
-  G.A. Brennecka, S. Weyer, M. Wadhwa, et al., 2010, Science, 327, 449, "²³⁸U/²³⁵U variations in meteorites: extant ²⁴⁷Cm and implications for Pb-Pb dating." See: <www.sciencemag.org/content/327/5964/449>.
- Chi Ma, O. Tschauner, J.R. Beckett, et al., 2012, American Mineralogist, 97, 1219, "Panguite, (Ti4⁺,Sc,Al,Mg,Zr,Ca)_1.8O₃, a new ultra-refractory titania mineral from the Allende meteorite: synchrotron micro-diffraction and EBSD." See: <www.its.caltech.edu/~chima/publications/2012_AM_buseckite.pdf>,
<media.caltech.edu/press_releases/13524>.

1969, Sep 28

Murchison Fireball and Meteorite. Near the town of Murchison (Victoria, Australia), a bright fireball was observed to separate into three fragments before disappearing, leaving a cloud of smoke. About 30 seconds later, a tremor was heard. Many specimens were found over an area larger than 13 km², with individual masses up to 7 kg; one piece, weighing 680 g, broke through a roof. The total collected mass exceeds 100 kg.
Ref:
-  P. Schmitt-Kopplin, Z. Gabelica, R.D. Gougeon, et al., 2010, Proc. Nat Acad. Sci. USA, 107, 2763, "High molecular diversity of extraterrestrial organic matter in Murchison meteorite revealed 40 years after its fall." See: <www.pnas.org/content/early/2010/02/12/0912157107.abstract>.
- S. Pizzarello, August 2012, Astrophysical Journal (Letters), 754, L27, "Hydrogen cyanide in the Murchison meteorite." See: <adsabs.harvard.edu/abs/2012ApJ...754L..27P>.
See also:
<tin.er.usgs.gov/meteor/metbull.php?code=16875>, <www.scientificamerican.com/article.cfm?id=murchison-meteorite>, <en.wikipedia.org/wiki/Murchison_meteorite>.

The Japanese Antarctic Research Expedition discovered nine meteorites on the blue ice field of the Yamato Mountains in Antarctica, December 1969. This was the first significant recovery of Antarctic meteorites and represented samples of several different types. In 2011, co-researchers from the USA, South Korea and Japan have found in meteorite Yamato 691 a new mineral, dubbed "Wassonite", formed from sulfur and titanium, and possessing a unique crystal structure that has not been previously observed in nature. 
Ref:
-  T. Nagata, 30 June, 1976, Meteoritics, 11, 181, "Yamato meteorites collected in Antarctica in 1969." See: <adsabs.harvard.edu/abs/1976Metic..11..181N>, <www.nasa.gov/centers/johnson/home/wassonite.html>.

27 NEAs known, of which 10 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

1970

First infrared diameter of an asteroid measured: 4 Vesta (H = 3.20 mag, D = 530 km, main-belt asteroid).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=4+Vesta&orb=1>, <en.wikipedia.org/wiki/4_Vesta>.
Ref:
-  D.A. Allen, 1970, Nature, 227, 158, "Infrared diameter of Vesta." See: <nature.com/nature/journal/v227/n5254/abs/227158a0.html>. 

Lost City Fireball. Four stations (Hominy OK, Woodward OK, Pleasanton KS, and Garden City KS) of the Prairie Meteorite Network simultaneously photographed the track of a meteoroid fireball. Analysis of the photographs indicated that a meteorite might have landed within an area east of Lost City (OK, USA). This was the first time in the US that simultaneous photography of a fireball from multiple observation points was achieved, making it possible to calculate a trajectory and delimit a search area on the ground. Six days later, a 9.83 kg (21.6 pound) meteorite was spotted sitting in a snow-covered dirt road within one-half mile of Lost City. Three additional smaller meteorite fragments were recovered later (272 g, 640 g, 6.6 kg).
Ref:
-  Z. Ceplecha, 1996, Astronomy & Astrophysics, 311, 329, "Luminous efficiency based on photographic observations of the Lost City fireball and implications for the influx of interplanetary bodies onto Earth." See: <adsabs.harvard.edu/abs/1996A%26A...311..329C>, <en.wikipedia.org/wiki/Lost_City,_Oklahoma>.

C.S. Beals, 1970, Nature, 225, 368, "Impact craters and the relative ages of Earth and Moon." See: <adsabs.harvard.edu/abs/1970Natur.225..368B>.

C.J. van Houten, I. van Houten-Groeneveld, P. Herget & T. Gehrels, 1970, Astronomy & Astrophysics Suppl., 2, 339, "The Palomar-Leiden Survey of faint Minor Planets." See: <adsabs.harvard.edu/abs/1970A%26AS....2..339>.

Asteroid 2010 TW54 (H = 27.5 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 6.3 LD. Minimum miss distance 0.3 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+TW54&orb=1>.
See also: 9 October 2010.

IAU Colloquium No. 12 on Physical studies of minor planets, Tucson (AZ, USA), 6-10 March 1971. Proceedings: T. Gehrels (ed.), 1971, NASA SP-267, "Physical studies of minor planets." See: <adsabs.harvard.edu/abs/1971NASSP.267.....G>.

1971, Apr 11

Asteroid 2002 JE9 (H = 21.3 mag, D ≈ 200 m, PHA) passed Earth at a nominal miss distance of 0.6 LD. Minimum miss distance 0.6 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002+JE9+&orb=1>, <en.wikipedia.org/wiki/2002_JE9>.
See also: 10 April 1927.

V.L. Masajtis, M.V. Mikhajlov, T.V. Selivanovskaya, 1972, Meteoritics, 7(1), 39, "The Popigay meteorite crater." See: <adsabs.harvard.edu/abs/1972IGRv...14..327M>.

V.L. Masaitis, M.V. Mikhailov, T.V. Selivanovskaya, 1972, Int. Geol. Rev., 14, 327, "Popigai Basin -- an explosion meteorite crater." See: <adsabs.harvard.edu/abs/1972Metic...7...39M>.

D.J. Milton, B.C. Barlow, R. Brett, et al., 1972, Science, 175, 1199, "Gosses Bluff impact structure, Australia." See: <adsabs.harvard.edu/abs/1972Sci...175.1199M>, <en.wikipedia.org/wiki/Gosses_Bluff_crater>.

1972, Aug 10

Great Daylight 1972 Fireball (US19720810), Earth-grazing asteroid, estimated D ≈ 3-14 m, 100-sec passage with 15 km/s through the Earth atmosphere, 57 km high over the Rocky Mountains from Utah (USA) to Alberta (Canada). Coinciding with the annual Perseid meteor shower. Suggestions that this object is still in an Earth crossing orbit around the Sun and passed close to the Earth again in August 1997 have not been substantiated (Spahr, 2010, private communication).
Ref:
-  R.D. Rawcliffe, C.D. Bartky, F. Li, et al., 1974, Nature, 247, 449, "Meteor of August 10, 1972." See: <adsabs.harvard.edu/abs/1974Natur.247..449R>;
- E.J. Öpik, 1974, Irish Astronomical Journal, 11, 165, "A meteorite that got away." See: <adsabs.harvard.edu/abs/1974IrAJ...11..165O>;
- A.C. Clarke, 1993, in preface of his novel The Hammer of God (New York: Bantam Books).  See: <en.wikipedia.org/wiki/The_Hammer_of_God>;
- E. Tagliaferri, 1998, Mercury, Vol. 27, no. 6, p. 18, "Observation of meteoroid impacts by space-based sensors." See: <adsabs.harvard.edu/abs/1998Mercu..27f..18T>;
- Z. Ceplecha, 1994, Astronomy & Astrophysics, 283, 287, "Earth-grazing daylight fireball of August 10, 1972." See: <adsabs.harvard.edu/abs/1994A%26A...283..287C>.
See also: <web.archive.org/web/20050120051405/www.maa.agleia.de/Comet/Other/1972.html>, <apod.nasa.gov/apod/ap090302.html>, <en.wikipedia.org/wiki/The_Great_Daylight_1972_Fireball>, <en.wikipedia.org/wiki/Earth-grazing_fireball>.

1973, Jan 

Eleanor F. Helin and Eugene M. Shoemaker begin photographic NEO searches using Palomar 46 cm (18 inch) telescope: the Planet-Crossing Asteroid Survey (PCAS), 1973 – 1978. They took photographic plates 3 nights each month and found first Earth orbit crosser (asteroid 5496, 1973 NA, H = 15.3 mag, D ≈ 3 km) on 4 July 1973.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1973+NA&orb=1>.
Ref:
-  E.F. Helin, E.M. Shoemaker, 1979, Icarus, 40, 321, "The Palomar Planet-crossing Asteroid Survey, 1973 – 1978." See: <adsabs.harvard.edu/abs/1979Icar...40..321H>, <en.wikipedia.org/wiki/Planet-Crossing_Asteroid_Survey>.

Asteroid 2009 BH2 (H = 22.4 mag, D ≈ 120 m) passed Earth at a nominal miss distance of 3.2 LD. Minimum miss distance 0.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2009+BH2&orb=1>.

P.D. Zimmerman, G.W. Wetherill, 1973, Science, 182,  51, "Asteroidal source of meteorites." See: <adsabs.harvard.edu/abs/1973Sci...182...51Z>.

Asteroid 2012 EN5 (H = 22.4 mag, D ≈ 120 m) passed Earth at a nominal miss distance of 9.3 LD. Minimum miss distance 0.3 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+EN5&orb=1>.

G.W. Wetherill, 1975, in: Proc. 6^th Lunar Science Conference, Houston (TX, USA), 17-21 March 1975, Vol. 2 (New York: Pergamon Press, Inc.), p. 1539, "Late heavy bombardment of the moon and terrestrial planets." See: <adsabs.harvard.edu/abs/1975LPSC....6.1539W >.

1975, Jan 23

Asteroid 433 Eros (1898 DQ, H = 11.16 mag, D = 34.4 × 11.2 × 11.2 km, orbital P = 1.76 yr, Amor asteroid), passed Earth at 59 LD (= 0.15 AU). 
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1898+DQ&orb=1>, <en.wikipedia.org/wiki/433_Eros>.

Asteroid 2012 FT35 (H = 29.3 mag, D ≈ 5 m) passed Earth at a nominal miss distance of 2.3 LD. Minimum miss distance 0.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+FT35&orb=1>.

D. Morrison, 1976, Astronomy, 4, no. 6, p. 6, "Asteroids." See: <adsabs.harvard.edu/abs/1976Ast.....4f...6M>.

1976, Jan 7

First discovery of an Aten asteroid (semi-major axis < 1 AU), 2062 Aten (1976 AA, H = 16.8 mag, D = 1.1 km), by Eleanor F. Helin (1932 – 2009, USA).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1976+AA&orb=1>, <en.wikipedia.org/wiki/2062_Aten>.
Ref:
-  E.F. Helin, E.M. Shoemaker, 1977, Icarus, 31, 415, "Discovery of asteroid 1976 AA".  See: <adsabs.harvard.edu/abs/1977Icar...31..415H>.

Gujarat Brilliant Fireball and Dhajala Meteorite Shower, India.
Ref:
- N. Bhandari, D. Lal, J.R. Trivedi, 1976, Meteoritics, 11, 137, "The Dhajala meteorite shower." See: <adsabs.harvard.edu/abs/1976Metic..11..137B>.

Jilin Meteorite Shower, near Jilin  City (Jilin Province, China), had a dispersion ellipse of 72 × 8.5 km and  landed over 100 fragments with a total mass > 2700 kg. The largest of these  fragments weighs 1770 kg and presents the largest stony meteorite known.
Ref:
-   K. Yau, P.  Weissman, D. Yeomans, 1994, Meteoritics,  29, 864, "Meteorite falls in China and some related human  casualty events." See: <adsabs.harvard.edu/abs/1994Metic..29..864Y>, <www.daviddarling.info/encyclopedia/J/Jilin.html>, <en.wikipedia.org/wiki/Meteorite_fall>.

Z. Ceplecha, R.E. McCrosky, 1976, Journal of Geophysical Research, 81, 6257, "Fireball end heights – a diagnostic for the structure of meteoric material." See: <adsabs.harvard.edu/abs/1976JGR....81.6257C>.

Asteroid 2012 EP10 (H = 29.2 mag, D ≈ 5 m) passed Earth at a nominal miss distance of 3.9 LD. Minimum miss distance 0.3 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+EP10&orb=1>.

Asteroid 2011 GA (H = 21.0 mag, D ≈ 200 m, PHA) passed Earth at a nominal miss distance of 2.4 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+GA&orb=1>.

Asteroid 2010 UY7 (H = 28.5 mag, D ≈ 7 m) passed Earth at a nominal miss distance of 9.3 LD. Minimum miss distance 0.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+UY7&orb=1>.
See also: 26 October 2010.

C.R. Chapman, J.G. Williams, W.K. Hartmann, 1978, Annual Review of  Astronomy & Astrophysics, 16, 33, "The asteroids." See: <adsabs.harvard.edu/abs/1978ARA%26A..16...33C>.

B.L. Narendra, 1978, Discovery 13(1), 10, "The Peabody Museum meteorite collection: a historic account." See: <peabody.yale.edu/collections/meteorites-and-planetary-science/weston-meteorite>,
<peabody.yale.edu/collections/meteorites-and-planetary-science/wethersfield-meteorite>.

G.L. Verschuur, 1978, Cosmic Catastrophes (Reading,   MA, USA:  Addison-Wesley Publ. Co.).  See: <adsabs.harvard.edu/abs/1978coca.book.....V>.

1978, Apr 1

IAU Minor Planet Center moved to Smithsonian Astrophysical Observatory, Cambridge (MA, USA). Brian G. Marsden, director. Up to this time, the set of numbered minor planets had increased to 2060, with nearly 180,000 observations in the archive.  See: <www.oaa.gr.jp/~oaacs/mp/BriefHistoryofMPCbyConradBardwell.pdf>, <www.iau.org/static/publications/IB104.pdf>, p. 67.

E. Bowell, C.R. Chapman, J.C. Grady, D. Morrison, B. Zellner, 1978, Icarus, 35, 313, "Taxonomy of asteroids." See: <adsabs.harvard.edu/abs/1978Icar...35..313B>.

1979

T. Gehrels (ed.), 1979, Asteroids I  (Tucson: Univ. Arizona Press).  See: <adsabs.harvard.edu/abs/1979aste.book.....G >.

E.J. Öpik, 1979, Irish Astronomical Journal, 14, 31, "Dinosaurs." See: <adsabs.harvard.edu/abs/1979IrAJ...14Q..31O >.

R.D. Rawcliffe, 1979, Astrophysical Journal, 228, 338, "Satellite observations of Meteors."  See: <adsabs.harvard.edu/abs/1979ApJ...228..338>.

G.W. Wetherill, 1979, Scientific American, 240, No. 3, 38, "Apollo objects."  See: <adsabs.harvard.edu/abs/1979SciAm.240...54W>.

The Vela Incident. Double flas explosion detected by an American Vela Hotel satellite over the South Atlantic caused by nuclear weapons test or meteoroid? See: <en.wikipedia.org/wiki/Vela_Incident>.

W.M. Napier, S.V.M. Clube, 1979, Nature, 282, 455, "A theory of terrestrial catastrophism."  See: <adsabs.harvard.edu/abs/1979Natur.282..455N>.

E.F. Helin, E.M. Shoemaker, 1979, Icarus, 40, 321, "The Palomar planet-crossing asteroid survey, 1973-1978." See: <adsabs.harvard.edu/abs/1979Icar...40..321H>.

H.H. Nininger, 1979, Meteoritics, 14, 497, " Small asteroids frequently arrive on the Earth."  See: <adsabs.harvard.edu/abs/1979Metic..14..497N>.

53 NEAs known, of which 17 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

1980

Spacewatch program started by Tom Gehrels and Robert S. McMillan, LPL, UA, Tucson (AZ, USA). Routine detections started in 1984, survey started in 1989. CCD-scanning observations are conducted 20 nights each lunation with the Steward Observatory 0.9-m Spacewatch Telescope (down to v = 21 mag) and the  Spacewatch 1.8-m telescope (down to v = 23 mag), both on Kitt Peak (AZ, USA). From 1992 to 1995 Spacewatch automatically detected more than 60,000 asteroids down to v = 21 mag.
Ref:
-  R.S. McMillan and The Spacewatch Team, 2007, in: A. Milani, G.B. Valsecchi & D. Vokrouhlický (eds.), Proc. IAU Symposium No. 236 on Near Earth Objects, our Celestial Neighbors: Opportunity and Risk, Prague (Czech Republic), 14-18 August 2006 (Cambridge: CUP), p. 329, "Spacewatch preparations for the era of deep all-sky surveys."  See: <adsabs.harvard.edu/abs/2007IAUS..236..329M>;
- D.K. Yeomans, S.R. Chesley, P.W. Chodas, 2010, in: A.M. Finkelstein, W.F. Huebner & V.A. Shor (eds.), Proc. Intern. Conf. Asteroid-Comet Hazard 2009, Protecting the Earth against collisions with asteroids and comet nuclei, St. Petersburg (Russian Federation), 21-25 September 2009 (Saint Petersburg: Nauka), p. 244, "NASA's Near-Earth Object Program Office."  See: <ftp://quasar.ipa.nw.ru/pub/ACHBOOK_2009/ach-2009_book.pdf >, <www.skyandtelescope.com/news/125432648.html>.
- R.S. McMillan, T.H. Bressi, J.V. Scotti, et al., 2012, American Astronomical Society, DPS meeting #44, #210.14, "Spacewatch observations of Near-Earth Objects." See: <adsabs.harvard.edu/abs/2012DPS....4421014M>.
See also: <spacewatch.lpl.arizona.edu/>, <en.wikipedia.org/wiki/Spacewatch>.

E. Helin, D. Morrison, G. Wetherill, M. Hanner, 1980, Sky & Telescope, 60, 12, "IRAS and the asteroids."  See: <adsabs.harvard.edu/abs/1980S%26T....60...12H>.

Asteroid 2009 WW7 (H = 28.9 mag, D ≈ 6 m) passed Earth at a nominal miss distance of 5.6 LD. Minimum miss distance 0.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2009+WW7&orb=1>.

1980, Jun

Nobel Prize winning physicist Luiz W. Alvarez (1911 – 1988, USA) and colleagues published their seminal paper (1980), associating the extinction of dinosaurs ~65.5 Myr ago with the direct impact of a large asteroid or comet. Ten years later after this initial proposal, evidence of a huge impact crater called Chicxulub, off the coast of Yucatán Peninsula (Mexico), strongly confirmed their theory. The crater center is located near the town Chicxulub. The crater diameter is over 180 km, maybe even 300 km, making the feature one of the largest confirmed impact craters on Earth. The crater was discovered by the geophysicist Glen Penfield, who had been looking for oil in Yucatán during the late-1970s. Returning later he found evidence for the impact theory (A.R. Hildebrand et al., 1991). The impacting NEO that formed the crater had a diameter D = 10 ± 4 km; the explosion released an energy of about 5 × 10⁷ megaton TNT, substantially more powerful than the largest known volcanic eruption. W.F. Bottke et al. (2007) suggested that the impacting NEO was a member of the Baptistina family of asteroids, created by a collision  of two main-belt asteroids (with D = 170 km and 60 km) 160 Myr ago, the largest surviving orbiting member of which is main-belt asteroid 298 Baptistina (D = 13-30 km), discovered in 1890 by Auguste H. Charlois (1864 – 1910) at the Observatoire de Nice (France). But see Masiero et al. (2011). Schulte et al. (2010) summarized evidence that the Chicxulub impact triggered the mass extinction ~65.5 year ago.
Ref:
-   L. Alvarez, W. Alvarez, S. Klint, 1980, Science News, 117(2), 22, 12 January 1980, "Asteroid-caused extinctions." Correction: Science News, 117(6), .., 9 February 1980.  See: <www.sciencenews.org/view/feature/id/188305/title/Now_--_Asteroid-Caused_Extinctions>, <www.sciencenews.org/view/feature/id/177017/title/Correction_Now_--_Asteroid-Caused_Extinctions>, <adsabs.harvard.edu/abs/1980SciN..117...22A>;
- J. Smit, J. Hertogen, 1980, Nature, 225, 198, 22 May 1980, "An extraterrestrial event in the Cretaceous-Tertiary boundary." See: <adsabs.harvard.edu/abs/1980Natur.285..198S>;
- L.W. Alvarez, W. Alvarez,  F. Asaro, H.V. Michel, 1980, Science, 208, 1095, 6 June 1980, "Extraterrestrial cause for the Cretaceous–Tertiary [K-T] extinction." See: <adsabs.harvard.edu/abs/1980Sci...208.1095A>;
- J. Smit, J. Hertogen, L.W. Alvarez, W. Alvarez, F.  Asaro, H.V. Michel, E.M. Shoemaker, 1980, Sky & Telescope, 80, 188, "Fresh light on an ancient catastrophe –  Cretaceous-Tertiary extinction event." See: <adsabs.harvard.edu/abs/1980S%26T....60R.188S>;
- D.V. Kent, G.C. Reid, R.E. Brown, L.W. Alvarez, et al. 1981, Science, 211, 648, 13 February 1981, "Asteroid extinction hypothesis." See: <adsabs.harvard.edu/abs/1981Sci...211..648K>;
- J. Smit, G. Klaver, 1981, Nature, 292, 47, 2 July 1981, "Sanadine spherules at the Cretaceous-Tertiary boundary indicate a large impact event." See: <www.nature.com/nature/journal/v292/n5818/abs/292047a0.html>, <adsabs.harvard.edu/abs/1981Natur.292...47S>;
- R.P. Turco, O.B. Toon, C. Park, et al., 1981, Science,  214, 19, "Tunguska meteor fall of 1908 – effects on stratospheric ozone." See: <adsabs.harvard.edu/abs/1981Sci...214...19T>.
- R.A.F. Grieve, 1984, Nature, 310, 370, "Cretaceous-Tertiary extinctions: physical evidence of impact." See: <adsabs.harvard.edu/abs/1984Natur.310..370G>;
- A.R. Hildebrand, G.T. Penfield, D.A. Kring,  et al., 1991, Geology,19, 867, "Chicxulub Crater: A possible Cretaceous/Tertiary boundary impact crater on the Yucatán Peninsula, Mexico." See: <adsabs.harvard.edu/abs/1984Natur.310..370G>;
- K.O. Pope, K.H. Baines, A.C. Ocampo, B.A. Ivanov, 1994, Earth and Planetary Science Letters, 128, 719, "Impact winter and the Cretaceous/Tertiary extinctions: results of a Chicxulub asteroid impact model." See: <adsabs.harvard.edu/abs/1994E%26PSL.128..719P>;
- G.L. Verschuur, 1996, Impact! The threat of comets and asteroids (Oxford: OUP), Ch.2 "The saga of the  Chicxulub Crater." See: <adsabs.harvard.edu/abs/1996itca.book.....V>;
- P. Claeys, S. Goderis, 2007, Nature, 449, 30, "Lethal billiards." See: <adsabs.harvard.edu/abs/2007Natur.449...30C>;
- W.F. Bottke, D. Vokrouhlický, D. Nesvorný, et al., 2007, Nature, 449, 48,  "An asteroid breakup 160 Myr ago as the probable source of the K/T impactor." See: <adsabs.harvard.edu/abs/2007Natur.449...48B>;  
- D.J. Majaess, D. Higgins, L.A. Molnar, et al., 2009, Journal of the Royal Astronomical Society of Canada, 103, 7, "New constraints on the asteroid 298 Baptistina, the alleged family member of the K/T impactor." See: <adsabs.harvard.edu/abs/2009JRASC.103....7M>;
- P. Schulte, L. Alegret, I. Arenillas, et al., 5 March 2010, Science, 327, 1214 , "The Chicxulub asteroid impact and mass extinction at the Cretaceous-Paleogene boundary." See: <www.sciencemag.org/content/327/5970/1214.abstract?sid=e1f5d964-44c1-471c-a76c-ee04a627676f>;
- J.D. Archibald, W.A. Clemens, K. Padian, et al., 21 May 2010, Science, 328, 973, "Cretaceous-Extinctions: multiple causes." See: <www.sciencemag.org/search?site_area=sci&y=9&x=32&fulltext=Cretaceous-Extinctions%3A%20multiple%20causes&submit=yes>;
- P. Schulte, L. Alegret, I. Arenillas, et al., 21 May 2010, Science, 328, 975, "Cretaceous-Extinctions: multiple causes / responses."  See: <www.sciencemag.org/content/328/5981/975.full>.
- J.R. Masiero, A.K. Mainzer, T. Grav, et al., 2011, Astrophysical Journal, 741, 68, "Main belt asteroids with WISE/NEOWISE. I. Preliminary albedos and diameters." See: <adsabs.harvard.edu/abs/2011ApJ...741...68M>.
- H. Pälike, 8 February 2013, Science, 339, 655, "Impact and extinction." See: <www.sciencemag.org/content/339/6120/655.summary>.
- P.R. Renne, A.L. Deono, F.J. Hilgen, et al., 2013, Science, 339, 684, "Time scales of critical events around the Cretaceous-Paleogene boundary." See: <www.sciencemag.org/content/339/6120/684.abstract>.
See also: <en.wikipedia.org/wiki/Chicxulub_crater>,  <www.unb.ca/passc/ImpactDatabase/images/chicxulub.htm>, <www.colorado.edu/news/releases/2004/168.html>, <en.wikipedia.org/wiki/Extinction_event>, <www.jyi.org/volumes/volume5/issue6/features/weinreb.html>, <www.jyi.org/volumes/volume5/issue7/features/weinreb.html>, <www.scientificamerican.com/article.cfm?id=asteroid-killed-dinosaurs>, <www.sciencedaily.com/releases/2007/01/070118094039.htm>, <www.jpl.nasa.gov/asteroidwatch/newsfeatures.cfm?release=2011-296>.

Tajikistan Fireball, 5 August 1980, observed by the meteor observing stations operated by the Meteor Patrol of the Hissar Astronomical Observatory (Tajikistan) and Kipchak station.
Ref:
- N.A. Konovalova, J.M. Madiedo, J.M. Trigo-Rodríguez, 2013, LPI Contribution No. 1719, p. 1479, "Analysis of a large meteorite-dropping fireball from the Apollo NEA family." See: <adsabs.harvard.edu/abs/2013LPICo1719.1479K>.

Asteroid 2011 TO (H = 26.3 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 9.0 LD. Minimum miss distance 0.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+TO&orb=1>.
See also: 28 September 2011, 27 September 2044.

R.A.F. Grieve, 1981, Nature, 291, 16, "Impact cratering."  See: <adsabs.harvard.edu/abs/1981Natur.291...16G>.

Asteroid 143651 (2003 QO104, H = 16.0 mag, D ≈ 2200 km, PHA) passed Earth at a nominal miss distance of 2.8 LD. Minimum miss distance 2.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003+QO104&orb=1>.

1981, Jul 13-16

First NASA NEO workshop on Collision of Asteroids and Comets with the Earth: Physical and Human Consequences, Snowmass (CO, USA), chaired by Eugene M. Shoemaker. Report never published.
Ref:
-   D. Chandler, 2008, Nature, 453, 1164, "The burger bar that saved the world."  See: <www.nature.com/news/2008/080625/full/4531164a.html>.

First Snowbird Conference on Large Body Impacts and Terrestrial Evolution: Geological, Climatological, and Biological Implications. Snowbird (Utah, USA).  See: <www.lpi.usra.edu/lpi_40th/1981.shtml>.

C. Emiliani, E.B. Kraus, E.M. Shoemaker, 1981, Earth and Planetary Science Letters, 55, 317, "Sudden death at the end of Mesozoic."  See: <adsabs.harvard.edu/abs/1981E%26PSL..55..317E>.

G.W. Wetherill, 1981, Icarus, 48, 308, "Which fireballs are meteorites – a study of the Prairie Network photographic meteor data."  See: <adsabs.harvard.edu/abs/1981Icar...48..308W>.

Asteroid 2012 TY52 (H = 21.1 mag, D ≈ 200 m, PHA) passed Earth at a nominal miss distance of 1.1 LD. Minimum miss distance 0.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+TY52+&orb=1>.

The Wethersfield Fireball and Meteorite. See: <peabody.yale.edu/collections/meteorites-and-planetary-science/wethersfield-meteorite>.

E.M. Shoemaker, 1983, Annual Review of Earth and Planetary Science, 11, 461, "Asteroid and comet bombardment of the Earth."  See: <adsabs.harvard.edu/abs/1983AREPS..11..461S>.

Discovery of the Chesapeak Bay impact crater, formed by a bolide that impacted the eastern shore of North America ~35 million years ago. It is the largest impact crater in the USA.
Ref:
-  Wuchang Wei, C.W. Poag, L.J. Poppe, et al., 1993, Geology, 21, 478, "Deep sea drilling Project Site 612 bolide event: new evidence of a late Eocene impact-wave deposit and a possible impact site, U.S. east coast: comment and reply."  See: <geology.geoscienceworld.org/cgi/content/abstract/21/5/478>;
- C. Koeberl, W.U. Reimold, D. Brandt, C.W. Poag, 1995, Meteoritics, 30, 528, "Chesapeak Bay  crater, Virginia: confirmation of impact origin."  See: <adsabs.harvard.edu/abs/1995Metic..30R.528K>.
See also: <woodshole.er.usgs.gov/epubs/bolide/>, <en.wikipedia.org/wiki/Chesapeake_Bay_impact_crater>.

1983, Jun 20-22

International conference on Asteroids, Comets, Meteors, Uppsala (Sweden). Proceedings: C.-I. Lagerkvist & H. Rickman, 1983, Asteroids, Comets, Meteors (Uppsala: Astronomiska Observatoriet).  See: <adsabs.harvard.edu/abs/1983acmp.book.....L>.

Asteroid 3200 Phaethon (1983 TB, H = 14.51 mag, D = 5.1 km, M = 1.4 × 10¹⁴ kg, PHA) discovered by IRAS. It approaches the Sun closer than any other numbered asteroid: its perihelion is 0.14 AU, i.e., less than half Mercury's perihelion distance. Phaethon is possibly an old comet core. Its closest approach to Earth within the next 190 yr will occur on 14 December 2093 at 7.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1983+TB&orb=1>, <en.wikipedia.org/wiki/3200_Phaethon>.
Ref:
-  J. Davies, S.F. Gree, C.M. Bardwell, et al., 1983, IAU Circular 3860, "Comet IRAS (1983o)."  See: <cepsar.open.ac.uk/pers/s.f.green/p4_6.shtml>;
- J. Licandro, H. Campins, T. Mothé-Diniz, et al., 2007, Astronomy & Astrophysics, 461, 751, "The nature of comet-asteroid transition object (3200) Phaethon.."  See: <adsabs.harvard.edu/abs/2007A%26A...461..751L>;
- J. de León, H. Campins, K. Tsiganis, et al., 2010, Astronomy & Astrophysics,  513, 26, "Origin of the near-Earth asteroid Phaethon and the Geminids meteor shower."  See: <adsabs.harvard.edu/abs/2010A%26A...513A..26D>;
- D. Jewitt, J. Li, 2010, Astronomical Journal, 140, 1519, "Activity in Geminid parent (3200) Phaethon."  See: <adsabs.harvard.edu/abs/2010AJ....140.1519J>.
See also: <www.cfa.harvard.edu/iauc/03800/03878.html>, <en.wikipedia.org/wiki/Geminids>, <science.nasa.gov/science-news/science-at-nasa/2010/06dec_geminids/>.

The 0.9-m Spacewatch Telescope became the first telescope to detect and discover asteroids and comets with electronic detectors (CCDs, as opposed to photographic plates or films).  See: <spacewatch.lpl.arizona.edu/>.

Z. Sekanina, D.K. Yeomans, 1984, Astronomical Journal, 89, 154, "Close encounters and collisions of comets with the earth." See: <adsabs.harvard.edu/abs/1984AJ.....89..154S>.

C.J. van Houten, P. Herget, B.G. Marsden, 1984, Icarus, 59, 1, "The Palomar-Leiden Survey of Faint Minor Planets – conclusion."  See: <adsabs.harvard.edu/abs/1984Icar...59....1V>.

H.J. Melosh, 1984, Icarus, 59, 234, "Impact ejection, spallation, and the origin of meteorites."  See: <adsabs.harvard.edu/abs/1984Icar...59..234M>.

1985

Fred L. Whipple (1906 – 2004, USA): “Protection of the Earth from undesirable impacting bodies is not just a science fiction project for some improbable future. The cost might be comparable to, even smaller than, the world’s current military expenditures. We could choose to do it now. We could choose to protect ourselves from asteroids and comets rather than from each other.”
Ref:
-  F.L. Whipple, 1985, The Mystery of Comets (Baltimore: Smithsonian Institution Press).

D.I. Steel, W.J. Baggaley, 1985, Monthly Notices Royal Astronomical Society, 212, 817, "Collisions in the Solar System. I. Impacts of the Apollo-Amor-Aten asteroids upon the terrestrial planets."  See: <adsabs.harvard.edu/abs/1985MNRAS.212..817S>.

Asteroid 2012 PB20 (H = 24.9 mag, D ≈ 40 m) passed Earth at a nominal miss distance of 1.2 LD. Minimum miss distance 0.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+PB20+&orb=1>.

G. Hahn, H. Rickman, 1985, Icarus, 61, 417, "Asteroids in cometary orbits."  See: <adsabs.harvard.edu/abs/1985Icar...61..417H>.

G.W. Wetherill, 1985, Meteoritics, vol. 20, March 31, p. 1, "Asteroidal source of ordinary chondrites."  See: <adsabs.harvard.edu/abs/1985Metic..20....1W>.

G.W. Wetherill, 1985, Science, 228, 877, "Occurrence of giant impacts during the growth of the terrestrial planets."  See: <adsabs.harvard.edu/abs/1985Sci...228..877W>.

1985, Jun 3-6

International conference on Asteroids, Comets, Meteors, II, Uppsala (Sweden). Proceedings: C.-I. Lagerkvist, H. Rickman, B.A. Lindblad, H. Lundstedt, 1986, Asteroids, Comets, Meteors II (Uppsala: Astronomiska Observatoriet).  See: <adsabs.harvard.edu/abs/1986acm..proc.....L>.

L.A. McFadden, M.J. Gaffey, Th.B. Mccord, 1985, Science, 229, 160, "Near-Earth Asteroids: possible sources from reflectance spectroscopy." See: <adsabs.harvard.edu/abs/1985Sci...229..160M>.

1985, Sep 2

Asteroid 2007 CN26 (H = 21.0 mag, D ≈ 200 m, PHA) passed Earth at at a nominal miss distance of 1.0 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2007+CN26+&orb=1>.

I. Halliday, A.T. Blackwell, A.A. Griffin, 28 November 1985, Nature, 318, 317, "Meteorite impacts on humans and buildings." See: <www.nature.com/nature/journal/v318/n6044/abs/318317a0.html>.

S.F. Green, N. Eaton, A.J. Meadows, J.K. Davies, B.C. Stewart, 1985, Icarus, 64, 517, "The detection of fast-moving asteroids and comets by IRAS."  See: <adsabs.harvard.edu/abs/1985Icar...64..517G>.

R.A.F. Grieve, V.L. Sharpton, A.K. Goodacre, 1985, Earth and Planetary Science Letters, 76, 1, "A perspective on the evidence for periodic cometary impacts on Earth."  See: <adsabs.harvard.edu/abs/1985E%26PSL..76....1G>.

Asteroid 2011 CL50 (H = 27.6 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 3.3 LD. Minimum miss distance 0.7 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+CL50&orb=1>.

D.L. Matson, 1986, The IRAS Asteroid and Comet Survey, JPL D-3689 (Pasadena: JPL).
See also: <irsa.ipac.caltech.edu/IRASdocs/surveys/comet.html>.

D.I. Steel, W.G. Elford, 1986, Monthly Notices Royal Astronomical Society, 218, 185, "Collisions in the Solar System. III. Meteoroid survival times."  See: <adsabs.harvard.edu/abs/1986MNRAS.218..185S>.

ESA spacecraft Giotto flyby of comet Halley.
Ref:
-  J. Kissel, D.E. Brownlee, K. Buchler, et al., 1986, Nature, 321, 336, "Composition of comet Halley dust particles from Giotto observations."  See: <adsabs.harvard.edu/abs/1986Natur.321..336K>;
- G. Schwehm, 2006, ESA Bulletin, 125, 8, "Twenty years after Giotto - ESA's pioneering mission to comet Halley."   See: <adsabs.harvard.edu/abs/2006ESABu.125....8S>.
See also: <hubble.esa.int/science-e/www/object/index.cfm?fobjectid=31876>, <hubble.esa.int/science-e/www/area/index.cfm?fareaid=15>, <www.esa.int/SPECIALS/Rosetta/SEMMA0YTVKG_0.html>, <www.esa.int/esaSC/SEMUAYJ4LOG_index_0.html>, <www.esa.int/esaSC/SEM18PD1XOG_index_0.html>.

R.N. Pugh, J.E. Allen, 1986, presented at the 49th Annual Meeting of the Meteoritical Society, American Museum of Natural History, New York (NY, USA), LPI Contribution 600, p.208, "Origing of the Willamette Meteorite." See: <adsabs.harvard.edu/abs/1986LPICo.600E.208P>, <en.wikipedia.org/wiki/Willamette_Meteorite>.

Asteroid 2006 XR4 (H = 26.2 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 9.0 LD. Minimum miss distance 1.0 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2006+XR4&orb=1>.

R.A.F. Grieve, 1987, Annual Reviews of Earth and Planetary Sciences, 15, 245, "Terrestrial impact structures."  See: <adsabs.harvard.edu/abs/1987AREPS..15..245G>.

D.K. Yeomans, S.J. Ostro, P.W. Chodas, 1987, Astronomical Journal, 94, 189, "Radar astrometry of near-earth asteroids."  See: <adsabs.harvard.edu/abs/1987AJ.....94..189Y>.

Z. Ceplecha, P. Spurný, J. Bocek, et al., 1987, Bulletin Astronomical Institutes of Czechoslovakia, 38, 211, "European Network fireballs photographed in 1978."  See: <adsabs.harvard.edu/abs/1987BAICz..38..211C>.

Z. Ceplecha, 1988, Bulletin of the Astronomical Institutes of Czechoslovakia, 38, 222, "Geometric, dynamic, orbital and photometric data on meteoroids from photographic fireball networks."  See: <adsabs.harvard.edu/abs/1987BAICz..38..222C>.

T. Gehrels, 1988, On the Glassy Sea. An Astronomer's Journey (New York: American Institute of Physics), Ch. 16, p. 183, "Asteroid impacts and planet formation."  See: <adsabs.harvard.edu/abs/1988gsaa.book.....G>. Including the history  of the 90 cm Spacewatch Telescope on Kitt Peak (AZ, USA).

K.A. Maher, D.J. Stevenson, 1988, Nature, 331, 612, "Impact frustration of the origin of life."  See: <adsabs.harvard.edu/abs/1988Natur.331..612M>.

1988, Mar 8-11

International conference on Asteroids II, Tucson (AZ, USA). Proceedings: R.P. Binzel, T. Gehrels, & M.S. Matthews (eds.), 1989, Asteroids II (Tucson: Univ. Arizona Press).  See: <adsabs.harvard.edu/abs/1989aste.conf.....B>.

H.J. Melosh, 1988, Nature, 332, 687, "The rocky road to panspermia."  See: <adsabs.harvard.edu/abs/1988Natur.332..687M>.

Z. Ceplecha, 1988, Bulletin Astronomical Institutes of Czechoslovakia, 39, 221, "Earth's influx of different populations of sporadic meteoroids from photographic and television data."  See: <adsabs.harvard.edu/abs/1988BAICz..39..221C>.

T. Gehrels, 1988, in: Reports of Planetary Astronomy (NASA: Washington), p. 45, "CCD scanning for comets and asteroids."  See: <adsabs.harvard.edu/abs/1988plas.rept...45G>.

G.W. Wetherill, 1988, Icarus, vol. 76, 1, "Where do the Apollo objects come from?"  See: <adsabs.harvard.edu/abs/1988Icar...76....1W>.

Asteroid 2010 UK (H = 26.8 mag, D ≈ 15 m) passed Earth at at a nominal miss distance of 0.8 LD. Minimum miss distance 0.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010+UK+&orb=1>.

Second Snowbird Conference on Global Catastrophes in Earth History: Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality, Snowbird (Utah, USA). Proc.: V.L. Sharpton & P.D. Ward (eds.), 1991, Geol. Soc. of America Special Paper, Vol. 247.  See: <www.lpi.usra.edu/lpi_40th/1988.shtml>.

E.M. Shoemaker, C.S. Shoemaker, R.F. Wolfe, 1988, in: V.L. Sharpton & P.D. Ward (eds.), 1991, Proc. Second Snowbird Conference on Global Catastrophes in Earth History: Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality, Snowbird (Utah, USA), "Asteroid and comet flux in the neighbourhood of the Earth."  See: <www.lpi.usra.edu/lpi_40th/1988.shtml>.

1989

T. Gehrels begins full NEO search operation using CCC drift-scan mode at the Spacewatch Telescope, on Kitt Peak (AZ, USA).  See: <spacewatch.lpl.arizona.edu/>.

C.R. Chapman, D. Morrison, 1989, Cosmic Catastrophes (New York: Plenum).  See: <adsabs.harvard.edu/abs/1989coca.book.....C>.

H.J. Melosh, 1989, Impact cratering: a geologic process (New York: Oxford University Press).  See: <adsabs.harvard.edu/abs/1989icgp.book.....M>, <adsabs.harvard.edu/abs/1989S%26T....78T.382M>.

D.L. Matson, G.J. Veeder, E.F. Tedesco,  L.A. Lebofsky, 1989, in: Asteroids II, R.P. Binzel, et al. (eds.), Proc. Conf. in Tucson (AZ, USA) 8-11 March 1988,  (Univ. Arizona Press), p. 269, "The IRAS asteroid and comet survey".  See: <adsabs.harvard.edu/abs/1989aste.conf..269M>.
A total of 1811 asteroids and 25 comets with known orbits were measured. Evidence was found in the IRAS data base for a large population of asteroids with unknown orbits.
See also: D.L. Matson, IPAC, JPL D-3698, 1986, <irsa.ipac.caltech.edu/IRASdocs/surveys/comet.html>.

Conrad M. Bardwell (1926 – 2010), Temmon Guide, 1989, "A brief history of the Minor Planet Center."  See: <www.oaa.gr.jp/~oaacs/mp/BriefHistoryofMPCbyConradBardwell.pdf>.

Re-discovery of the largest known PHA: 4179 Toutatis 1989 AC (H = 15.3 mag, D = 4.6×2.4×1.9 km, P = 4.03 yr). It was first sighted on February 10, 1934, as object 1934 CT, and then promptly lost. Re-discovery on January 4, 1989, by Christian Pollas (France), and was named after the Celtic god Toutatis/Teutates, known to popular culture as the God the cartoon character Astérix's chief Vitalstatistix evokes so that the sky may never fall on his head. Radar imagery has shown  that Toutatis is a irregular body consisting of two distinct "lobes", with maximum widths of about 4.6 km and 2.4 km respectively. It is hypothesized that Toutatis formed from two originally separate bodies which coalesced at some point, with the resultant asteroid being compared to a "rubble pile".
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1989+AC&orb=1>, <en.wikipedia.org/wiki/Toutatis-4179>.
Ref:
-  J.-L. Heudier, R. Chemin, A. Maury, C. Pollas, January 1989, IAU Circ., 4701, 2, "1989 AC."  See: <adsabs.harvard.edu/abs/1989IAUC.4701....2H>;
- S.J. Ostro, R.S. Hudson, R.F. Jurgens, et al., 1995, Science, 270, 80, "Radar images of asteroid 4179 Toutatis."  See: <adsabs.harvard.edu/abs/1995Sci...270...80O>;
- R.S. Hudson, S.J. Ostro, 1995, Science, 270, 84, "Shape and non-principal axis spin state of asteroid 4179 Toutatis."  See: <adsabs.harvard.edu/abs/1995Sci...270...84H>;
- D.J. Scheeres, S.J. Ostro, R.S. Hudson, et al., 1998, Icarus, 132, 53, "Dynamics of orbits close to asteroid 4179 Toutatis."  See: <adsabs.harvard.edu/abs/1998Icar..132...53S>;
- S.J. Ostro, R.S. Hudson, K.D. Rosema, et al., 1999, Icarus, 137, 122, "Asteroid 4179 Toutatis: 1996 radar observations."  See: <adsabs.harvard.edu/abs/1999Icar..137..122O>;
- R.S. Hudson, S.J. Ostro, D.J. Scheeres, 2003, Icarus, 161, 346, "High-resolution model of asteroid 4179 Toutatis."   See: <adsabs.harvard.edu/abs/2003Icar..161..346H>;
- A.M. MacRobert, 2004, Sky & Telescope, 108 (3), 82, "The Closest Whiz-by of Toutatis."  See: <adsabs.harvard.edu/abs/2004S%26T...108c..82M>, <br.groups.yahoo.com/group/Astronomynews/message/5177>.
See also: <science.nasa.gov/science-news/science-at-nasa/2000/ast31oct_1/>, <newton.dm.unipi.it/neodys/index.php?pc=1.1.8&n=Toutatis>.

G.W. Wetherill, 1989, Meteoritics, 24, 15, "Cratering of the terrestrial planets by Apollo objects."  See: <adsabs.harvard.edu/abs/1989Metic..24...15W>.

1989, Mar 22

Asteroid 4581 Asclepius (1989 FC, H = 20.4 mag, D ≈ 300 m, PHA) passed Earth at at a nominal miss distance of 1.8 LD (≈ 107 R_Earth ≈ 680,000 km). Minimum miss distance 1.8 LD. The next pass to come within 3 LD will not take place until 2189.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1989+FC&orb=1>, <en.wikipedia.org/wiki/4581_Asclepius>.
Ref:
-  C.R. Chapman, D. Morrison, E. Bowell, 1989, in: 52^nd Annual Meeting of the Meteoritical Society, 31 July 31 – 4 August, Vienna (Austria), LPI Contr. 712, Meteoritics, 24, 258,  "Hazards from Earth-approachers: implications of 1989 FC's 'Near Miss'."
See also: <adsabs.harvard.edu/abs/1989LPICo.712...33C>, <adsabs.harvard.edu/abs/1989Metic..24S.258C>.
See also: 16 August 2012 and 24 March 2051.

G. Hahn, P. Magnusson, A.W. Harris, et al., 1989, Icarus, 78, 363, "Physical studies of Apollo-Amor asteroids - UBVRI photometry of 1036 Ganymed and 1627 Ivar." See: <adsabs.harvard.edu/abs/1989Icar...78..363H>.

A. Milani, M. Carpino, G. Hahn, A.M. Nobili, 1989, Icarus, 78, 212, "Dynamics of planet-crossing asteroids – classes of orbital behavior. Project SPACEGUARD."  See: <adsabs.harvard.edu/abs/1989Icar...78..212M>.

G.J. Veeder, M.S. Hanner, D.L. Matson, et al., 1989, Astronomical Journal, 97, 1211, "Radiometry of Near-Earth Asteroids."  See: <adsabs.harvard.edu/abs/1989AJ.....97.1211V>.

S. van den Bergh, 1989, Publ. Astron. Soc. Pacific, 101, 500, "Life and death in the inner solar system."  See: <adsabs.harvard.edu/abs/1989PASP..101..500V>, <www.astronomynotes.com/solfluf/s5.htm>.

1989, Jun 12-16

International conference on Asteroids, Comets, Meteors, III, Uppsala (Sweden). Proceedings: C.-I. Lagerkvist, H. Rickman, B.A. Lindblad, & M. Lindgren, 1990, Asteroids, Comets, Meteors III (Uppsala: Astronomiska Observatoriet).  See: <adsabs.harvard.edu/abs/1990acmi.book.....L>.

1989, Aug 19-22

First-ever radar images of an asteroid: 4769 Castalia (1989 PB, NEA, H = 16.9 mag, D = 1.8 × 0.8 km, PHA) obtained with the 305 m Arecibo radio telescope by Steven J. Ostro (1946 – 2008) of NASA JPL, Pasadena (CA, USA) and R. Scott Hudson of Caltech, Pasadena. At the time of observation the distance to 4769 Castalia was d = 11 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1989+PB&orb=1>, <en.wikipedia.org/wiki/4769_Castalia>.
Ref:
-  S.J. Ostro, J.F. Chandler, A.A. Hine, et al., 1990, Science, 248, 1523, "Radar images of asteroid 1989 PB."  See: <adsabs.harvard.edu/abs/1990Sci...248.1523O>.
As of May 2008, Ostro and his collaborators had detected 222 NEAs (including 130 PHAs and 24 binaries) and 118 main-belt objects with radar.  See: <impact.arc.nasa.gov/news_detail.cfm?ID=180>.

J. Luu, D. Jewitt, 1989, Astronomical Journal, 98, 1905, "On the relative numbers of C types and S types among near-earth asteroids." See: <adsabs.harvard.edu/abs/1989AJ.....98.1905L>.

D.M. Raup, P.A. Sabine, P. Ashmole, et al., 1989, Philosophical Transactions of the Royal Society of London, series B, Biological Sciences, vol. 325, No. 1228, Evolution and Extinction, p. 421, "The case for extraterrestrial causes of extinction."  See: <adsabs.harvard.edu/abs/1989RSPTB.325..421R>, <www.jstor.org/stable/pdfplus/2396933.pdf?acceptTC=true>.

N.H. Sleep, K.J. Zahnle, J.F. Kasting, H.J. Morowitz, 1989, Nature, 342, 139, "Annihilation of ecosystems by large asteroid impacts on the early Earth."  See: <adsabs.harvard.edu/abs/1989Natur.342..139S>.

C.R. Chapman, D. Morrison, 1989, Mercury, 18, 185, "Cosmic impacts, cosmic catastrophes."  See: <adsabs.harvard.edu/abs/1989Mercu..18..185C>.

134 NEAs known, of which 42 PHAs.  See: <neo.jpl.nasa.gov/stats/>.

S.V.M. Clube, W.M. Napier, 1990, The Cosmic Winter (Oxford: Blackwell).  See: <adsabs.harvard.edu/abs/1990cowi.book.....C>.

From 1990 until its termination in 1996, Duncan Steel, director of Spaceguard Australia and Vice-President of The Spaceguard Foundation (see 26 March 1996), directed the southern hemisphere program Anglo-Australian Near Earth Asteroid Survey (AANEAS) for the discovery and tracking of near-Earth asteroids, based at the Anglo-Australian Observatory, using the UK 1.2m Schmidt Telescope.
Ref:
-  D.I. Steel, R.H. McNaught, G.J. Garradd, D.J. Asher, K.S. Russell, 1997, Australian J. Astron., 7, 67, "AANEAS: a valedictory report."  See: <adsabs.harvard.edu/abs/1997AuJA....7...67S>, <users.tpg.com.au/users/tps-seti/spacegd4.html>, <www.sis-group.org.uk/abstract/steel2.htm>, <en.wikipedia.org/wiki/Anglo-Australian_Near-Earth_Asteroid_Survey>.

R.A.F. Grieve, 1990, Scientific American, 262(4), 66, "Impact cratering on the Earth."  See: <adsabs.harvard.edu/abs/1990SciAm.262...44G>.

E.F. Helin, R.S. Dunbar, 1990, Vistas in Astronomy, 33, 21, "Search techniques for near-earth asteroids."  See: <adsabs.harvard.edu/abs/1990VA.....33...21H>.

E.M. Shoemaker, R.F. Wolfe, C.S. Shoemaker, 1990, in: Global catastrophes in Earth history. An interdisciplinary conference on impacts, volcanism, and mass mortality, Special Paper Geological Society of America, 247, 155, "Asteroid and comet flux in the neighbourhood of Earth."

Chapman, C.R., Morrison, D., 1990, Mercury, 19, 21; 19, 30, "Cosmic impacts, cosmic catastrophes. II."  See: <adsabs.harvard.edu/abs/1990Mercu..19...21C>.

D. Morrison, C.R. Chapman, 1990, Sky & Telescope, 79, 261, "Target Earth – it will happen."  See: <adsabs.harvard.edu/abs/1990S%26T....79..261M>.

1990, Apr

American Institute of Aeronautics and Astronautics (AIAA),  recommendations concerning NEOs to US Congress in a Position Paper Dealing with the Threat of an Asteroid Striking the Earth.  See: <pdf.aiaa.org//downloads/publicpolicypositionpapers/Asteroid-1990.pdf>.

Glanerbrug meteorite. A fireball seen by  hundreds of people in the Netherlands, Germany and Denmark resulted in an impact  of an 885 g meteorite, riddling the roof of a home in Glanerbrug (the  Netherlands).  See: <www.sterrenkunde.nl/index/encyclopedie/meteoren.html>, <nl.wikipedia.org/wiki/Glanerbrug_meteoriet>, <en.wikipedia.org/wiki/Meteorite_fall>.

C.R. Chapman, 1990, Nature, 344, 813, "Meteorite parent bodies."  See: <adsabs.harvard.edu/abs/1990Natur.344..813C>.

1990, Sep

US Congress House in NASA Multiyear Authorization Act of 1990: "imperative that detection rate of Earth-orbit-crossing asteroids must be increased substantially, and that means to destroy or alter orbits … should be defined and agreed internationally."

1990, Sep 19

Asteroid 2003 SW130 (H = 29.1 mag, D ≈ 5 m) passed Earth at at a nominal miss distance of 0.5 LD. Minimum miss distance 0.5 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003+SW130+&orb=1>.
See also: 19 September 2003, 19 September 2062.

1990, Oct 13

Earth-grazing fireball, a 40 kg asteroid passing 98 km above Czechoslovakia and Poland with 41.5 km/s.
Ref:
-  P. Spurný, Z. Ceplecha, J. Borovička, 1991, WGN, the Journal of the IMO, 19, 13, "Earth-grazing fireball: Czechoslovakia, Poland, October 13, 1990, 03h27m16sUT."  See: <adsabs.harvard.edu/abs/1991JIMO...19...13S>;
- J. Borovička, Z. Ceplecha, 1992, Astronomy & Astrophysics, 257, 323, "Earth-grazing fireball of October 13, 1990."  See: <adsabs.harvard.edu/abs/1992A%26A...257..323B>.
See also: <en.wikipedia.org/wiki/Earth-grazing_fireball>.

A. Milani, M. Carpino, F. Marzari, 1990, Icarus, 88, 292, "Statistics of close approaches between asteroids and planets: project SPACEGUARD."  See: <adsabs.harvard.edu/abs/1990Icar...88..292M>.

1991

US Congresssional Statement 1991: "The House Committee on Science and Technology believes that it is imperative that the detection rate of Earth‐orbit‐crossing asteroids must be increased substantially, and that the means to destroy or alter the orbits of asteroids when they do threaten collisions should be defined and agreed upon internationally. The chances of the Earth being struck by a large asteroid are extremely small, but because the consequences of such a collision are extremely large, the Committee believes it is only prudent to assess the nature of the threat and prepare to deal with it." NASA Authorization Bill, 1991.
The US Congress House Committee on Science and Technology used NASA Authorization Bill to direct NASA to study (1) a programme to increase detection rate of Earth-orbit-crossing asteroids addressing costs, schedule, technology and equipment (Spaceguard Survey Report); (2) systems and technologies to destroy or alter orbits of such asteroids if they should pose a danger to life on Earth (NEO Interception Workshop).  See: <impact.arc.nasa.gov/gov_cong_hearings_1.cfm>.

1991

The 5000^th minor planet was numbered at the IAU Minor Planet Center, main-belt asteroid 5000 IAU (1987 QN7, H = 14.1 mag, D ≈ 5 km), discovered on 23 August 1987 by Eleanor F. Helin (1932 – 2009) at Palomar Observatory (CA, USA).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1987+QN7&orb=1>, <en.wikipedia.org/wiki/5000_IAU>.

1991, Jan 18

Asteroid 1991 BA (H = 28.7 mag, D ≈ 6 m) passed Earth at a nominal miss distance of 0.4 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1991+BA+&orb=1>, <en.wikipedia.org/wiki/1991_BA>.
Ref:
-  D. Steel, 1991, Nature, 354, 265, "Our asteroid-pelted planet".  See: <adsabs.harvard.edu/abs/1991Natur.354..265S>;
- J.V. Scotti, D.L. Rabinowitz, B.G. Marsden, 1991, Nature, 354, 287, "Near miss of the Earth by a small asteroid."  See: <adsabs.harvard.edu/abs/1991Natur.354..287S>.

D.L. Rabinowitz, 1991, Astronomical Journal, 101, 1518, "Detection of earth-approaching asteroids in near real time."  See: <adsabs.harvard.edu/abs/1991AJ....101.1518R>.

Asteroid 2012 UE34 (H = 23.1 mag, D ≈ 85 m) passed Earth at a nominal miss distance of 0.7 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+UE34&orb=1>.
See also: 8 April 2041.

1991, Apr – May

Workshop on Hazards Due to Comets and Asteroids (1), San Juan Capistrano (CA, USA). Proceedings: T. Gehrels, M.S. Matthews & A.M. Schumann (eds.), 1994, Hazards Due to Comets and Asteroids (Tucson: Univ. Arizona Press).  See: <adsabs.harvard.edu/abs/1994hdtc.conf.....G>, <www.ips.gov.au/IPSHosted/neo/info/refers/Bk_Hazards_Gehrels.htm>.

Benešov Bolide detected and observed at the Czech stations of the European Fireball Network on 7 May 1991, one of the brightest and best-documented bolides.
Ref:
-  J. Borovička, O.P. Popova, I.V. Nemtchinov, et al., 1998, Astronomy & Astrophysics, 334, 713, "Bolides produced by impacts of large meteoroids into the Earth's atmosphere: comparison of theory with observations. I. Benešov Bolide dynamics and fragmentation."  See: <adsabs.harvard.edu/abs/1998A%26A...337..591B>;
- N.G. Barri, V.P. Stulov, 2003, Solar System Research, 37, 302, "Peculiarities of the fragmentation of Benešov's Bolide."  See: <adsabs.harvard.edu/abs/2003SoSyR..37..302B>.

1991, Jun 24-28

International conference on Asteroids, Comets, Meteors, IV, Flagstaff, (AZ, USA). Proceedings: A.W. Harris & E.L.G. Bowell (eds.), 1992, Asteroids, Comets, Meteors 1991 (Houston: Lunar & Planetary Institute).  See: <adsabs.harvard.edu/abs/1992acm..proc.....H>.

1991, Jun 30 – Jul 3
          Sep 24-25
          Nov 5

NASA International NEO Detection Workshops, (1^st ) San Juan Capistrino Research Institute; (2^nd) NASA Ames Research Center; (3^rd ) Palo Alto (CA, USA).

1991, Aug

IAU XXI General Assembly, Buenos Aires (Argentina). Resolution by IAU Commission 20 on Positions and Motions of Asteroids, Comets and Satellites, under the presidency of Richard West, calling for an IAU Inter-Commission Working Group on Near Earth Objects (WG-NEO). See: <web.mit.edu/rpb/wgneo/>,  
<spaceguard.iasf-roma.inaf.it/SGF/history.html>.

R.A.F. Grieve, 1991, Meteoritics, 26, 175, "Terrestrial impact – the record in the rocks." See: <adsabs.harvard.edu/abs/1991Metic..26..175G>.

G.L. Verschuur, 1991, Astronomy, 19, No. 9, p. 50, "The end of civilization." See: <adsabs.harvard.edu/abs/1991Ast....19...50V>.

J.V. Scotti, D.L. Rabinowitz, B.G. Marsden, 1991, Nature, 354, 287, "Near miss of the earth by a small asteroid." See: <adsabs.harvard.edu/abs/1991Natur.354..287S>.

S.J. Ostro, R.F. Jurgens, K.D. Rosema, R. Winkler, D.K. Yeomans, D.B. Campbell, J.F. Chandler, I.I. Shapiro, A.A. Hine, R. Velez, 1991, Astronomical Journal, 102, 1490, "Asteroid radar astrometry." See: <adsabs.harvard.edu/abs/1991AJ....102.1490O>.

All-Union conference The Asteroid Hazard, St. Petersburg (Russian Federation). Proceedings in Russian.

1991, Oct 29

NASA spacecraft Galileo flew by asteroid 951 Gaspra (1916 S45, H = 11.46 mag, D = 18.2 × 10.5 × 8.9 km, main-belt asteroid) at a distance of 1600 km.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1916+S45&orb=1>, <en.wikipedia.org/wiki/951_Gaspra>.
Ref:
-  J. Veverka, M. Belton, K. Klaasen, C. Chapman, 1994, Icarus, 107, 2, "Galileo's encounter with 951 Gaspra: overview." See: <adsabs.harvard.edu/abs/1994Icar..107....2V>.

G.L. Verschuur, 1991, Air and Space, vol. 6, Oct.-Nov. 1991, p. 88, "This target earth." See: <adsabs.harvard.edu/abs/1991AirSp...6...88V>.

J.V. Scotti, D.L. Rabinowitz, B.G. Marsden, 1991, Nature, 354, 287, "Near miss of the earth by a small asteroid." See: <adsabs.harvard.edu/abs/1991Natur.354..287S>.

S.J. Ostro, 1991, Meteoritics, 26, 381, "Radar constraints on asteroid metal abundances and meteorite associations." See: <adsabs.harvard.edu/abs/1991Metic..26R.381O>.

A. Cellino, V. Zappalà, P. Farinella, 1991, Monthly Notices Royal Astronomical Society, 253, 561, "The size distribution of main-belt asteroids from IRAS data." See: <adsabs.harvard.edu/abs/1991MNRAS.253..561C>.
The IRAS data base on asteroid albedos and diameters has been used to derive size distributions for a set of ~4000 numbered main-belt asteroids.

T. Gehrels, 1991, Space Science Reviews, 58, 347, "Scanning with charge-coupled devices." See: <adsabs.harvard.edu/abs/1991SSRv...58..347G>.

E. Tollmann, A. Tollmann, 1992, Mitt. Österr. Geol. Ges., 84, 1, "The Flood Impact." On Tollmann's hypothetical bolide. See: <en.wikipedia.org/wiki/Tollmann's_hypothetical_bolide>.

C. Sagan, 1992, Bulletin of the  Atomic Scientists, 48, 24, "Between enemies." See: <en.wikiquote.org/wiki/Carl_Sagan>.

Near-Earth Object Interception Workshop, Los Alamos (USA), January 1992. Report: G.H. Canavan, J. Solem, October 1992, see: <adsabs.harvard.edu/abs/1992STIN...9322403C>, <impact.arc.nasa.gov/gov_earthasteroids_3jr.cfm>.

Workshop on Hazards Due to Comets and Asteroids (2), Los Alamos (NM, USA). Proceedings: T. Gehrels, M.S. Matthews & A.M. Schumann (eds.), 1994, Hazards Due to Comets and Asteroids (Tucson: Univ. Arizona Press). See: <adsabs.harvard.edu/abs/1994hdtc.conf.....G>, <www.ips.gov.au/IPSHosted/neo/info/refers/Bk_Hazards_Gehrels.htm>.

1992, Jan 25

The Spaceguard Survey: Report of the NASA International NEO Detection Workshop, D. Morrison (ed.), 1992 (Washington DC:   NASA). Delivered to US Congress. Recommends a search programme and international collaboration to find objects with D > 1 km; and the provision of six ground based telescopes, northern and southern hemisphere sites, southern hemisphere radar; half costs to come from international partners. See: <impact.arc.nasa.gov/downloads/spacesurvey.pdf>, <impact.arc.nasa.gov/news_detail.cfm?ID=59>, <impact.arc.nasa.gov/news_detail.cfm?ID=4>, <impact.arc.nasa.gov/news_detail.cfm?ID=24>, <impact.arc.nasa.gov/news_detail.cfm?ID=99>, <impact.arc.nasa.gov/news_detail.cfm?ID=109>, <impact.arc.nasa.gov/news_detail.cfm?ID=133>,  <impact.arc.nasa.gov/news_detail.cfm?ID=143>,
<impact.arc.nasa.gov/news_detail.cfm?ID=162>.
The term Spaceguard loosely refers to a number of efforts to discover and study NEOs. The British author Arthur C. Clarke (1917 – 2008) coined the name in his novel Rendezvous with Rama (1973, London: Victor Gollancz) where Spaceguard was the name of an early warning system. The name was later adopted by a number of real life efforts to discover and study NEOs. The IAU Working Group on Near-Earth Objects (WG-NEO) presented a paper in September 1995 entitled Beginning the Spaceguard Survey, which led on 26 March 1996 to the international organization called the Spaceguard Foundation (SGF).
Ref:
-  A.W. Harris, 2008, Nature, 453, 1178, "What Spaceguard did." See: <adsabs.harvard.edu/abs/2008Natur.453.1178H>, <spaceguard.iasf-roma.inaf.it/SGF/history.html>.

G.L. Verschuur, 1992, Astronomy, 20(4), 46, "Mysterious sungrazers." See: <adsabs.harvard.edu/abs/1992Ast....20...46V>.

Asteroid 2009 TD17 (H = 27.7 mag, D ≈ 10 m) passed Earth at a nominal miss distance of 7.6 LD. Minimum miss distance 0.8 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2009+TD17&orb=1>.
See also: 5 October 2009.

1992, Jan 14-16

NASA NEO Interception Workshop, Los Alamos (NM, USA). Full investigation of counter-measures concluded that nuclear explosives in stand-off mode most likely to succeed. Proceedings: G. Canavan, J. Solem, D.G.Rather (eds.), 1993, LANL 12476-C. See: <adsabs.harvard.edu/abs/1994hdtc.conf...93C>, <impact.arc.nasa.gov/downloads/spacesurvey.pdf>.

M. Pilkington, R.A.F. Grieve, 1992, Reviews of Geophysics, 30, 161, "The geophysical signature of terrestrial impact craters." See: <adsabs.harvard.edu/abs/1992RvGeo..30..161P>.

G.H. Canavan, J. Solem, May-June 1992, Mercury, 21(3), 107, "Interception of near-earth objects." See: <adsabs.harvard.edu/abs/1992Mercu..21..107C>.

D. Morrison, 1992, Mercury, 21, 103, "The Spaceguard Survey – protecting the earth from cosmic impacts." See: <adsabs.harvard.edu/abs/1992Mercu..21..103M>.

1992, Jul 6-12

International conference on Meteoroids and their parent bodies, Smolenice (Slovakia). Proceedings: J. Stohl & I.P. Williams (eds.), 1993 (Bratislava: Astronomical Institute, Slovak Academy of Sciences). See: <adsabs.harvard.edu/abs/1993mtpb.conf.....S>.

ESA spacecraft Giotto flyby of comet Grigg-Skjellerup.
Ref:
-  J.A.M. McDonnell, N. McBride, R. Beard, et al., 1993, Nature, 362, 732, "Dust particle impacts during the Giotto encounter with comet Grigg-Skjellerup." See: <adsabs.harvard.edu/abs/1993Natur.362..732M>;
- S.M.P. McKenna-Lawlor, P.W. Daly, E. Kirsch, et al., 1993, Nature, "Energetic ions at comet Grigg-Skjellerup measured from the Giotto spacecraft." See: <adsabs.harvard.edu/abs/1993Natur.363..326M>.
See also: <hubble.esa.int/science-e/www/area/index.cfm?fareaid=15>, <www.esa.int/SPECIALS/Rosetta/SEMMA0YTVKG_0.html>.

R.P. Binzel, S. Xu, S.J. Bus, E. Bowell, 1992, Science, 257, 779, "Origins for the Near-Earth Asteroids." See: <adsabs.harvard.edu/abs/1992Sci...257..779B>.

Z. Ceplecha, 1992, Astronomy & Astrophysics, 263, 361, "Influx of interplanetary bodies onto earth." See: <adsabs.harvard.edu/abs/1992A%26A...263..361C>.

1992, Oct 9

Peekskill Fireball and Meteorite. A fireball was seen streaking across the sky from Kentucky to New York. At least 14 people captured part of the fireball on videotape. A 12-kilogram stony meteorite (chondrite) from the fireball fell in Peekskill (NY, USA), smashed the trunk of a parked automobile and came to rest beneath it.
Ref:
-  Z. Ceplecha, P. Brown, R.L. Hawkes, 1994, Meteoritics, 29, 455, "Video observations of the Peekskill meteorite fireball: atmospheric trajectory and orbit." See: <adsabs.harvard.edu/abs/1994Metic..29Q.455C>;
- P. Brown, Z. Ceplecha, R.L. Hawkes, et al., 1994, Nature, 367, 624, "The orbit and atmospheric trajectory of the Peekskill meteorite from video records." See: <adsabs.harvard.edu/abs/1994Natur.367..624B>.
See also: <starchild.gsfc.nasa.gov/docs/StarChild/solar_system_level2/peekskill.html>,  <csep10.phys.utk.edu/astr161/lect/meteors/impacts.html>,  <uregina.ca/~astro/mb_5.html>, <www.lifeslittlemysteries.com/1535-when-space-attacks-6-craziest-meteor-impacts-history.html>, <apod.nasa.gov/apod/ap021118.html>, <apod.nasa.gov/apod/ap061119.html>, <apod.nasa.gov/apod/ap110123.html>.

T.J. Ahrens,  A.W. Harris, 1992, Nature, 360, 429, "Deflection and fragmentation of near-Earth asteroids." See: <adsabs.harvard.edu/abs/1992Natur.360..429A>.

Asteroid 4179 Toutatis (1989 AC, H = 15.3 mag, D = 4.6×2.4×1.9 km, orbital P = 4.03 yr, PHA) passed Earth at 9.4 LD. It is the largest known PHA.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1989+AC&orb=1>, <en.wikipedia.org/wiki/4179_Toutatis>.
Ref:
- R.S. Hudson, S.J. Ostro, D.J. Scheeres, 2003, Icarus, 161, 346, "High-resolution model of asteroid 4179 Toutatis." See: <adsabs.harvard.edu/abs/2003Icar..161..346H>.
See also: <science.nasa.gov/science-news/science-at-nasa/2000/ast31oct_1/>, <newton.dm.unipi.it/neodys/index.php?pc=1.1.8&n=Toutatis>.

1993

NASA Planetary Astronomy Program Office begins ramp up of funding for NEO observations.

Major L.N. Johnson, 1993, White Paper, presented to SPACECAST 2020,"Preparing for Planetary Defense: detection and interception of asteroids on collision course with Earth." In this paper the term Planetary Defense was coined. See: <csat.au.af.mil/2020/index.htm>, <www.fas.org/spp/military/docops/usaf/2020/app-r.htm>.

1993

Photographic asteroid and comet search project started by Timothy B. Spahr and C. Hergenrother (LPL, Univ. of Arizona). This project eventually evolved into the Catalina Sky Survey in 1998.
Ref:
-  T.B. Spahr, C. Hergenrother, S.M. Larson, 1993, Bulletin of the American Astronomical Society, 25, 1059. "High ecliptic latitude asteroid and comet search." See: <adsabs.harvard.edu/abs/1993DPS....25.1013S>.

Arthur C. Clarke (1917 - 2008, UK/Sri Lanka), 1993, The Hammer of God (London: Victor Gollancz Ltd). See: <en.wikipedia.org/wiki/The_Hammer_of_God>.

R.A.F. Grieve, 1993, Vistas in Astronomy, 36, 203, "Impact craters: lessons from and for the Earth." See: <adsabs.harvard.edu/abs/1993VA.....36..203G>.

F.E. Wickman, 1993, Swedish Geol. Journal, 115, 29, "Eight  pound ball fell on the ship and killed two boatsmen." An eight-pound  meteorite hit the Dutch VOC ship Malacca, sailing  from Holland to Batavia (Java, Netherlands-Indies) in 1648, allegedly killing two  sailors. Story based on book Reesa till Ostindien jempte een kort berättelse  om konungerijket Japan (1674) by 17^th century Swedish historian-turned sailor Olof Eriksson  Willman, who travelled the Netherlands-Indies in 1647 – 1653.
See also: <sv.wikipedia.org/wiki/Olof_Eriksson_Willman>.

1993, Jan 7-12

Workshop on Hazards Due to Comets and Asteroids (3), Tucson (AZ, USA). Proceedings: T. Gehrels, M.S. Matthews & A.M. Schumann (eds.), 1994, Hazards Due to Comets and Asteroids (Tucson: Univ. Arizona Press). See: <adsabs.harvard.edu/abs/1994hdtc.conf.....G>, <www.ips.gov.au/IPSHosted/neo/info/refers/Bk_Hazards_Gehrels.htm>.

1993, Jan 19

Lugo Fireball and Airburst (Northern, Italy). See: <www.ta3.sk/caosp/Eedition/FullTexts/vol24/pp117-124.pdf>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

P. Farinella, R. Gonczi, Ch. Froeschlé, C. Froeschlé, 1993, Icarus, 101, 174, "The injection of asteroid fragments into resonances." See: <adsabs.harvard.edu/abs/1993Icar..101..174F>.

J.G. Hills, M.P. Goda, 1993, Astronomical Journal, 105, 1114, "The fragmentation of small asteroids in the atmosphere." See: <adsabs.harvard.edu/abs/1993AJ....105.1114H>.

European Science Foundation (ESF) initiates new scientific network "Impact Cratering and Evolution of Planet Earth." This led to the submission of a Research Networking Programme proposal in 1998 "Response of the Earth System to Impact Processes (IMPACT)", approved for five years, 1998 to 2002. Four workshops were held in 2002 – 2003."
See <www.esf.org/impact>.

1993, Mar 24

U.S. Congressional Hearing on NEOs and Planetary Defense: "The Threat of Large Earth-Orbit Crossing Asteroids." See: <impact.arc.nasa.gov/gov_earthasteroids_1.cfm>.

D.L. Rabinowitz, 1993, Astrophysical Journal, 407, 412, "The size distribution of the Earth-approaching asteroids." See: <adsabs.harvard.edu/abs/1993ApJ...407..412R>.

J.C. Solem, 1993, Journal of Spacecraft and Rockets, 30 (2), 222, "Interception of comets and asteroids on collision course with Earth." See: <adsabs.harvard.edu/abs/1993JSpRo..30..222S>.

1993, May

Workshop on Hazards Due to Comets and Asteroids (4), Erice (Italy). Proceedings: T. Gehrels, M.S. Matthews & A.M. Schumann (eds.), 1994, Hazards due to Comets and Asteroids (Tucson: Univ. Arizona Press). See: <adsabs.harvard.edu/abs/1994hdtc.conf.....G>, <www.ips.gov.au/IPSHosted/neo/info/refers/Bk_Hazards_Gehrels.htm>.

1993, May 20

Asteroid 1993 KA2 (H = 29.0 mag, D ≈ 6 m) passed Earth at a nominal miss distance of 0.4 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1993+KA2&orb=1>.

1993, Jun 14-18

IAU Symposium No. 160 on Asteroids, Comets, Meteors, V, Belgirate (Italy). Proceedings: A. Milani, M. Di Martino & A. Cellino (eds.), 1994, Asteroids, Comets, Meteors 1993 (Dordrecht: Kluwer). See: <adsabs.harvard.edu/abs/1994IAUS..160.....M>.

C.F. Chyba, 1993, Nature, 363, 701, "Explosions of small Spacewatch objects in the Earth's atmosphere." See: <adsabs.harvard.edu/abs/1993Natur.363..701C>.

D.L. Rabinowitz, T. Gehrels, J.V. Scotti, et al.,  1993, Nature, 363, 704,  "Evidence for a near-Earth asteroid belt." See: <adsabs.harvard.edu/abs/1993Natur.363..704R>.

D. Morrison, 1993, in: Proc. IAF 43^rd International Astronautical Congress, Washington DC (USA), 28 August – 5 September 1992, Acta Astronautica, 30, 11, "An international program to protect the earth from impact catastrophe: Initial steps." See: <www.sciencedirect.com/science/article/pii/009457659390095E>.

Tom Gehrels' Vainu Bappu Lecture, presented to the 6^th Asian-Pacific Regional IAU Meeting, 16-20 August, Pune (India). Ref.: T. Gehrels, 1995, J. Astrophys. Astr. Suppl., 16, 1, "The beauty and danger of comets and asteroids." See: <adsabs.harvard.edu/abs/1995JApAS..16....1G>.

1993, Aug 28

NASA spacecraft Galileo flew by asteroid 243 Ida (H = 9.94 mag, D = 59.8 × 25.4 × 18.6 km, main-belt asteroid) at a distance of 10,300 km, and discovered binary component Dactyl (D = 1.4 km), orbiting Ida at a distance of 56 km.
Ref:
-  E. Asphaug, 2004, in:  M.J.S. Belton, et al. (eds.), Mitigation of Hazardous Comets and Asteroids (Cambridge: CUP), p. 66, "Interior structures for asteroids and cometary nuclei." See: <adsabs.harvard.edu/abs/2004mhca.conf...66A>.
See also:  <www2.jpl.nasa.gov/galileo/sepo/cruise/ida/ida.html>, <en.wikipedia.org/wiki/243_Ida>.

P. Farinella, B. Chauvineau, 1993, Astronomy & Astrophysics, 279, 251, "On the evolution of binary Earth-approaching asteriods." See: <adsabs.harvard.edu/abs/1993A%26A...279..251F>.

Z. Ceplecha, P. Spurný, J. Borovička, J. Keclíková, 1993, Astronomy & Astrophysics, 279, 615, "Atmospheric fragmentation of meteoroids." See: <adsabs.harvard.edu/abs/1993A%26A...279..615C>.

H.J. Melosh, I.V. Nemchinov, 1993, Nature, 366, 21, "Solar asteroid diversion." See: <adsabs.harvard.edu/abs/1993Natur.366...21M>.

R.Z. Akhmetshin, V.V. Ivashkin, V.V. Smirnov, 1994, Astronomicheskij Vestnik, 28, 13, "An analysis of the possibility of asteroid hazard mitigation for the Earth by the impact of a spacecraft." See: <adsabs.harvard.edu/abs/1994AVest..28...13A>.

D.J. Asher, S.V.M. Clube, 1993, Quarterly Journal Royal Astronomical Society, 34, 481, "An extraterrestrial influence during the current Glacial-Interglacial." See: <adsabs.harvard.edu/abs/1993QJRAS..34..481A>.

1994

T. Gehrels, M.S. Matthews & A.M. Schumann (eds.), 1994, Hazards Due to Comets and Asteroids (Tucson: Univ. of Arizona Press). Proceedings of  four Workshops in April/May 1991, January 1992,  January 1993, and May 1993. See: <adsabs.harvard.edu/abs/1994hdtc.conf.....G>, <ips.gov.au/IPSHosted/neo/info/refers/Bk_Hazards_Gehrels.htm>.

R.Z. Akhmetshin, V.V. Ivashkin, V.V. Smirnov, 1994, Astronomicheskij Vestnik, 28, 13, "An analysis of the possibility of asteroid hazard mitigation for the Earth by the impact of a spacecraft." See: <adsabs.harvard.edu/abs/1994AVest..28...13A>.

D.J. Asher, S.V.M. Clube, W.M. Napier, D.I. Steel, 1994, Vistas in Astronomy, 38, 1, "Coherent catastrophism." See: <adsabs.harvard.edu/abs/1994VA.....38....1A>.

E. Kristan-Tollmann, A. Tolmann, 1994, Terra Nova, 6, 209, "The youngest big impact on Earth deduced from geological and historical evidence." See: <en.wikipedia.org/wiki/Tollmann's_hypothetical_bolide>.

A. Deutsch, C. Koeberl, J.D. Blum, et al., 1994, Terra Nova, 6,  644, "The impact-flood connection: does it exist?" See: <en.wikipedia.org/wiki/Tollmann's_hypothetical_bolide>.

A.W. Harris, 1994, Icarus, 107, 209, "Tumbling asteroids." See: <adsabs.harvard.edu/abs/1994Icar..107..209H>.

1994, Jan 6

C.R. Chapman, D.D. Morrison, 1994, Nature, 367, 33, "Impacts on the Earth by asteroids and comets: assessing the hazard." See: <adsabs.harvard.edu/abs/1994Natur.367...33C>.

1994, Jan 18

Cando Fireball and Airburst(Spain). See: <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.

P. Spurný, 1994, Planetary and Space Science, 42, 157, "Recent fireballs photographed in central Europe." See: <adsabs.harvard.edu/abs/1994P%26SS...42..157S>.

1994, Feb

US Congress House Committee on Science and Technology passed an amendment to NASA Authorization Bill directing NASA to report within a year with a programme to identify and catalogue, with help from the Department of Defense and space agencies of other countries, within 10 year, orbital characteristics of all comets and asteroids with D > 1 km and in an orbit that crosses Earth’s. See: <impact.arc.nasa.gov/gov_cong_hearings_1.cfm>.

1994, Feb 1

Marshall Islands Fireball and Airbursts. A large meteoroid impacted over the Pacific Ocean at 2.6° N, 164.1° E, 300 km south of Kosrae (Micronesia). The impact was observed by space-based infrared sensors operated by the U.S. Department of Defense and by visible wavelength sensors operated by the U.S. Department of Energy. During entry the object broke into several pieces, one of which detonated at 34 km and another at 21 km altitude. M ≈ 1.6×10⁵ kg - 4.4×10⁶ kg; D ≈ 4.4 - 13.5 m. See: <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.
Ref:
-  E. Tagliaferri, R. Spalding, C. Jacobs, Z. Ceplecha, 1995, Earth, Moon, and Planets, 68, 563; "Analysis of the Marshall Island Fireball of February 1, 1994." See: <adsabs.harvard.edu/abs/1995EM%26P...68..563T>;
- T.B. McCord, J. Morris, D. Persong, et al., 1995, Journal of Geophysical Research, 100, E2, 3245, "Detection of a meteoroid entry into the Earth's atmosphere on February 1, 1994." See: <adsabs.harvard.edu/abs/1995JGR...100.3245M>;
- E. Tagliaferri, 1998, Mercury, 27, no.6, p.18, "Observation of meteoroid impacts by space-based sensors." See: <adsabs.harvard.edu/abs/1998Mercu..27f..18T>.

1994, Mar 15

Asteroid 1994 ES1 (H = 28.6 mag, D ≈ 7 m) passed Earth at a nominal miss distance of 0.4 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1994+ES1+&orb=1>.

C. Sagan, S.J. Ostro, 1994, Nature, 368, 501, "Dangers of asteroid deflection." See: <adsabs.harvard.edu/abs/1994Natur.368..501S>.

Z. Ceplecha, 1994, Astronomy & Astrophysics, 286, 967, "Impacts of meteoroids larger than 1 M into the Earth's atmosphere." See: <adsabs.harvard.edu/abs/1994A%26A...286..967C>.

St-Robert Daylight Fireball and Meteorit Fall over the Canada-US border, travelling at a velocity of ~13 km/s, widely seen from the provinces of Quebec and Ontario and the states of New Hampshire, Vermont and New York at distances up to ~500 km. The rock fragmented spectacularly ~50 km NE of Montreal at an altitude of ~36 km; hundreds of fragments have been found  with pieces of up to 6.5 kg. 
Ref:
-  P. Brown, A.R. Hildebrand, D.W. Green, et al., 1996, Meteoritics, 31, 502, "The fall of the St-Robert meteorite." See: <adsabs.harvard.edu/abs/1996M%26PS...31..502B>;
- A.R. Hildebrand, P.G. Brown, J.F. Wacker, et al., 1997, Journal of the Royal Astronomical Society of Canada, 91, 261, "The St-Robert Bolide of June 14, 1994." See: <adsabs.harvard.edu/abs/1997JRASC..91..261H>, <en.wikipedia.org/wiki/St-Robert_meteorite>.

H.J. Melosh, E.A. Whitaker, 1994, Nature, 369, 713, "Lunar crater chains." See: <adsabs.harvard.edu/abs/1994Natur.369..713M>.

C. Sagan, S.J. Ostro, 1994, Issues in Science and Technology, Summer 1994, 67, "Long-range consequences of interplanetary collisions." See: <trs-new.jpl.nasa.gov/dspace/handle/2014/33108>.

W.F. Bottke, M.C. Nolan, R. Greenberg, 1994, Meteoritics, 29, 446, "Provenance of the spacewatch small Earth-approaching asteroids." See: <adsabs.harvard.edu/abs/1994Metic..29S.446B>.

1994, Jul 16-22

Comet Shoemaker-Levy 9 collides with Jupiter. Some 21 cometary fragments with diameters up to ~ 2 km caused massive explosions, temporarily visible on the surface of Jupiter.
Ref:
-  H.A. Weaver, P.D. Feldman, M.F. A'Hearn, et al., 1994,  Science, 263, 787, "Hubble Space  Telescope observations of comet Shoemaker-Levy 9 (1993e)." See: <adsabs.harvard.edu/abs/1994Sci...263..787W>;
- K. Zahnle, M.-M. Mac Low, 1994, Icarus, 108,1, "The collision of Jupiter and comet Shoemaker-Levy 9." See: <adsabs.harvard.edu/abs/1994Icar..108....1Z>;
- M.-M. Mac Low, K. Zahnle, 1994, Astrophysical Journal, 434, 33, "Explosion of comet Shoemaker-Levy 9 on entry into the Jovian atmosphere." See: <adsabs.harvard.edu/abs/1994ApJ...434L..33M>;
- G. Orton, M. A'Hearn, K. Baines, et al., 1995, Science, 267, 1277, "Collision of comet Shoemaker-Levy 9 with Jupiter observed by the NASA Infrared Telescope Facility." See: <adsabs.harvard.edu/abs/1995Sci...267.1277O>;
- H.A. Weaver, M.F. A'Hearn, C. Arpigny, et al., 1995, Science, 267, 1282, "The Hubble Space Telescope (HST) observing campaign on comet Shoemaker-Levy 9." See: <adsabs.harvard.edu/abs/1995Sci...267.1282W>;
- D.H. Levy, E.M. Shoemaker, C.S. Shoemaker, 1995, Scientific American, 273, 68, "Comet Shoemaker-Levy 9 meets Jupiter." See: <adsabs.harvard.edu/abs/1995SciAm.273...68L>;
- D.H. Levy,  1995, Impact Jupiter: the crash of comet  Shoemaker-Levy 9 (New York: Plenum Press). See: <adsabs.harvard.edu/abs/1995ijcc.book.....L>;
- J.K. Beatty, D.H. Levy, 1995, Sky & Telescope, 90, 18, "Crashes  to ashes: a comet's demise." See: <adsabs.harvard.edu/abs/1995S%26T....90...18B>;
- K.S. Noll, H.A. Weaver & P.D. Feldman (eds.),  2006, The impact of comet Shoemaker-Levy 9 on Jupiter,  Proc. IAU Coll. No.  156, Baltimore (MD, USA) 9-12 May 1995, STScI Symposium Series No. 9 (Cambridge:  CUP, ISBN-0521-03162-1). See: <www.iau.org/science/publications/iau/>.
See also: <www.stsci.edu/institute/conference/jupiter-impact>, <www2.jpl.nasa.gov/sl9/>, <en.wikipedia.org/wiki/Comet_Shoemaker-Levy_9>.

W. Tedeschi, E. Teller, 1994, Space Policy, 10, 183, "A plan for worldwide protection against asteroid impacts." See: <www.sciencedirect.com/science/article/pii/0265964694900671>.

Meeting on Small Bodies in the Solar System and their interactions with the planets, Mariehamn (Finland), 8 - 12 August 1994. Proc: H. Rickman, M.J. Valtonen (eds.), 1996, Earth, Moon, Planets, 72, No. 1 - 3, "Worlds in interaction: small bodies and planets of the solar system." See: <adsabs.harvard.edu/abs/1996EM%26P...72.....R>.

1994, Aug 20

IAU XXII General Assembly, Den Haag (the Netherlands). The IAU Working Group on Near Earth Objects, chaired by Andrea Carusi, had a science meeting, and presented a report recommending that an international authority should take responsibility for NEO investigations and initiatives.
Ref:
-  I. Appenzeller (ed.), 1996, Transactions IAU XXIIB, (Dordrecht: Kluwer Acad. Publ.), IAU Commission 20 Report, p. 164, "Working Group Meeting 2 on Near-Earth Object Detection." See: <adsabs.harvard.edu/abs/1996IAUTB..22.....A>;
-  J. Tate, 2000, Space Policy, 16, 261, "Avoiding collisions: the Spaceguard Foundation." See: <www.sciencedirect.com/science/article/pii/S0265964600000369>.
See also: <spaceguard.iasf-roma.inaf.it/SGF/history.html>.

P. Farinella, Ch. Froeschlé, C. Froeschlé, R. Gonczi, G. Hahn, A. Morbidelli, G.B. Valsecchi, 1994, Nature, 371, 314, "Asteroids falling into the Sun." See: <adsabs.harvard.edu/abs/1994Natur.371..315F>.

1994, Sep 26-30

1^st International Conference on Space Protection of the Earth (SPE-94), Chelyabinsk, Russian Federation.

D.L. Rabinowitz, 1994, Icarus, 111, 364, "The size and shape of the near-Earth asteroid belt."

K. Yau, P. Weissman, D. Yeomans, 1994, Meteoritics, 29, 864, "Meteorite falls in China and some related human casualty events." In February-March of the year 1490 a barrage of stones of 1 – 1.5 kg fell like rain in the Chíng-yang district of Shansi Province (China), killing more than 10,000 people. See: <adsabs.harvard.edu/abs/1994Metic..29..864Y>.
See also: <www.mail-archive.com/meteorite-list@meteoritecentral.com/msg80757.html>, <en.wikipedia.org/wiki/Impact_event>.

C. Covey, S.L. Thompson, P.R. Weissman, et al., 1994, Global and Planetary Change, 9, 263, "Global climatic effects of atmospheric dust from an asteroid or comet impact on Earth." See: <adsabs.harvard.edu/abs/1994GPC.....9..263C>.

K. Keil, H. Haack, E.R.D. Scott, 1994, Planetary and Space Science, 42, 1109, "Catastrophic fragmentation of asteroids: evidence from meteorites." See: <adsabs.harvard.edu/abs/1994P%26SS...42.1109K>.

K.O. Pope, K.H. Baines, A.C. Ocampo, B.A. Ivanov, 1994, Earth and Planetary Science Letters, 128, 719, "Impact winter and the Cretaceous/Tertiary extinctions: results of a Chicxulub asteroid impact model." See: <adsabs.harvard.edu/abs/1994E%26PSL.128..719P>.

1994, Dec 9

Asteroid 1994 XM1 (H = 28.2 mag, D ≈ 8 m) passed Earth at a nominal miss distance of 0.3 LD. Minimum miss distance 0.3 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1994+XM1+&orb=1>.
See also: <spacewatch.lpl.arizona.edu/pics.html>, <impact.arc.nasa.gov/news_detail.cfm?ID=96>, <www.rssd.esa.int/index.php?project=GAIA&page=picture_of_the_week&pow=5>.

S. Rozendaal, 1994, Elsevier, 17 december 1994, "De catastrophe. Waarom de dino's uitstierven en de mens ontstond."

1995

D. Steel, 1995, Rogue Asteroids and Doomsday Comets: the Search for the Million Megaton Menace that Threatens Life on Earth (New York: Wiley). With a foreword by Arthur C. Clarke. See: <adsabs.harvard.edu/abs/1995radc.book.....S>. Review by D. Morrison, 1997, Physics Today, 50, 65. See: <adsabs.harvard.edu/abs/1997PhT....50Q..65M>.

1995

The (1.0/1.2m) Schmidt CCD Asteroid Program (SCAP) of the Beijing Astronomical Observatory put in practice, a NEO search telescope in operation at the Xuyu Station of the Purple Mountain Observatory, 120 km north of Nanjing (China).
Ref:
-  Y. Ma, H. Zhao, D. Yao, 2007, in: A. Milani, G.B. Valsecchi & D. Vokrouhlický (eds.), Proc. IAU Symposium No. 236 on Near Earth Objects, our Celestial Neighbors: Opportunity and Risk, Prague (Czech Republic), 14-18 August 2006 (Cambridge: CUP), p. 381, "NEO search telescope in China." See: <adsabs.harvard.edu/abs/1997IAUJD...6E..24Z>.

SPACECAST 2020, "Preparing for planetary defense: detection and interception of asteroids on collision course with Earth." See: <csat.au.af.mil/2020/papers/app-r.pdf>.

D.I. Steel, R.H. McNaught, C.J. Garradd, et al., 1995, in: J. Chapman, R. Cannon & B. Hidayat (eds.), Proc. IAU Colloquium No. 148 on The Future Utilisation of Schmidt Telescopes, Bandung (Indonesia), 7-11 March 1994, ASP Conf. Series, 84, 159, "Searching for Near-Earth Asteroids with the UK Schmidt telescope at the AAO." See: <adsabs.harvard.edu/abs/1995ASPC...84..159S>.

J.G. Hills, P.J.T. Leonard, 1995, Astronomical Journal, 109, 401, "Earth-crossing asteroids: the last days before earth impact." See: <adsabs.harvard.edu/abs/1995AJ....109..401H>.

K. Muionen, E. Bowell, K. Lumme, 1995, Astronomy & Astrophysics, 293, 948, "Interrelating asteroid size, albedo, and magnitude distributions." See: <adsabs.harvard.edu/abs/1995A%26A...293..948M>.

Hanover Fireball (Germany). See: <apod.nasa.gov/apod/ap960226.html>.

S. Mottola, G. de Angelis, M. di Martino, et al., 1995, in: Abstracts of the Lunar and Planetary Science Conference, 26, 1003, "The EUNEASO photometric follow-up program." See <adsabs.harvard.edu/abs/1995LPI....26.1003M>.

R.P. Binzel, 1995, Planetary Report, 15, no. 2, p. 8, "Near-Earth objects: friends or foes?" See: <adsabs.harvard.edu/abs/1995PlR....15b...8B>.

D.I. Steel, 1995, Monthly Notices Royal Astronomical Society, 273, 1091, "Collisions in the Solar System. VI. Terrestrial impact probabilities for the known asteroid population." See: <adsabs.harvard.edu/abs/1995MNRAS.273.1091S>.

1995, Apr 24-26

United Nations international conference on Near Earth Objects. Proceedings: J.L. Remo (ed.), 1997, Near-Earth Objects: the United Nations International Conference, Annals New York Academy of Sciences, Vol. 822 (New York: NY Academy of Sciences).
See also: neutrino.aquaphoenix.com/un-esa/neo.html>, <www3.interscience.wiley.com/journal/119150668/issue>.

1995, May 22-26

Planetary Defense Workshop: An International Technical Meeting on Active Defense of the Terrestrial Biosphere from Impacts by Large Asteroids and Comets, Livermore (CA, USA). Proceedings: LLNL CONF-9505266. Report by Peter Tyson. See: < impact.arc.nasa.gov/news_detail.cfm?ID=93 >.

D. Steel, 1995, The Observatory, 115, 136, "Tunguska and the Kagarlyk meteorite." See: <adsabs.harvard.edu/abs/1995Obs...115..136S>.

1995, Jun

Report of the NASA Near Earth Objects Survey Working Group, E.M Shoemaker (ed.), 1995 (Washington DC: NASA Office of Space Science, Solar System Exploration Office). Released with a programme to meet Congress’ requirements, delivered to Congress 9 Aug 1995. Recommends NASA, USAF and international collaboration to provide two dedicated 2-m discovery telescopes, use of two existing 1 m telescopes for survey and follow-up, enhanced funding to obtain roughly half time on a 3 – 4 m telescopes for physical observation, and Minor Planet Center enhancements. See: <impact.arc.nasa.gov/downloads/neosurvey.pdf>, <impact.arc.nasa.gov/news_detail.cfm?ID=94>.

V.V. Svetsov, E.V. Nemtchinov, A.V. Teterev, 1995, Icarus, 116, 131, " Disintegration of large meteoroids in Earth's atmosphere: theoretical models." See: <adsabs.harvard.edu/abs/1995Icar..116..131S>.

S.I. Ipatov, 1995, Solar System Research, 29, 261, "Migration of small bodies to Earth." See: <adsabs.harvard.edu/abs/1995SoSyR..29..261I>.

D. Steel, 1995, Proceedings Astronomical Society of Australia, 12 (2), 202, "Asteroid discovery efficiencies for telescope systems at Siding Spring." See: <adsabs.harvard.edu/abs/1995PASA...12..202S>.

Ch. Froeschlé, G. Hahn, R. Gonczi, et al., 1995, Icarus, 117, 45, "Secular resonances and the dynamics of Mars-crossing and Near-Earth asteroids." See: <adsabs.harvard.edu/abs/1995Icar..117...45F>.

M. Beech, D. Steel, 1995, Quarterly Journal Royal Astronomical Society, 3, 281, "On the definition of the term Meteoroid." See: <adsabs.harvard.edu/abs/1995QJRAS..36..281B>.

R.P. Binzel, 1995, Meteoritics, 30, 486, "Forging new links in the asteroid-meteorite connection." See: <adsabs.harvard.edu/abs/1995Metic..30Q.486B>.

P. Hammerling, J.L. Remo, 1995, Acta Astronautica, 36, 337, "NEO interaction with nuclear radiation." See: <www.sciencedirect.com/science/article/pii/0094576595001115>.

D.A. Kring, H.J. Melosh, D.M. Hunten, 1995, Meteoritics, 30(5), 530, "Possible climatic perturbations produced by impacting asteroids and comets." See: <adsabs.harvard.edu/abs/1995Metic..30T.530K>.

S. Mottola, G. de Angelis, M. di Martino, 1995, Icarus, 117, 62, "The Near-Earth Objects follow-up program: first results." See: <adsabs.harvard.edu/abs/1995Icar..117...62M>.

C. Koeberl, W.U. Reimold, D. Brandt, C.W. Poag, 1995, Meteoritics, 30(5), 528, "Chesapeake Bay crater, Virginia: confirmation of impact origin." See: <adsabs.harvard.edu/abs/1995Metic..30R.528K>.

1995, Sep

American Institute of Aeronautics and Astronautics (AIAA) position paper Responding to the Potential Threat of a Near-Earth-Object Impact, prepared by its Space Systems Technical Committee and its Systems Engineering Technical Committee. See: <pdf.aiaa.org/downloads/publicpolicypositionpapers/NearEarth-1995.pdf>.

1995, Sep 18-22

IAU Working Group on Near Earth Objects Workshop, Vulcano (Italy), Beginning the Space Guard Survey. The Workshop participants agreed to set up a Spaceguard Foundation, which materialized on 26 September 1996, in Rome. The Spaceguard Central Node (SCN), hosted by ESA at ESRIN (Frascati, Italy) is a web site of The Spaceguard Foundation. Since 2002, the SCN is supporting ESA’s Science Programme in all issues related to NEOs.
Ref:
-  J. Tate, 2000, Space Policy, 16, 261, "Avoiding collisions: the Spaceguard Foundation." See: <www.sciencedirect.com/science/article/pii/S0265964600000369>.
See also:
<cfa-www.harvard.edu/~marsden/SGF/Vulcano/programme.ps>,  <spaceguard.iasf-roma.inaf.it/SGF/history.html>, <www.esa.int/esaMI/NEO/SEMS58OVGJE_0.html>.

D. Morrison, 1995, Astronomy, 23, No. 10, p. 34, "Target: Earth!" See: <adsabs.harvard.edu/abs/1995Ast....23...34M>.

D. Steel, 1995, Australian Journal of Astronomy,  6 (3), 87, "The death of the dinosaurs and protection of humankind from asteroid impacts: the first suggestion?" See: <adsabs.harvard.edu/abs/1995AuJA....6...87S>.

D. Steel, 1995, WGN, Journal of the International Meteor Organization, 23, 207, "Two "Tunguskas" in South America in the 1930's?" See: <adsabs.harvard.edu/abs/1995JIMO...23..207S>.

1995, Dec

Near Earth Asteroid Tracking (NEAT) program run by NASA and JPL to discover NEOs, from December 1995 to April 2007. The project employed two telescopes, on Maui (1m GEODSS telescope, HI, USA) and Mt. Palomar (1.2m Schmidt, CA, USA).
Ref:
-  S.H. Pravdo, D.L. Rabinowitz, E.F. Helin, et al., 1999, Astronomical Journal, 117, 1616, "The Near-Earth Asteroid Tracking (NEAT) program: an automated system for telescope control, wide-field imaging, and object detection." See: <adsabs.harvard.edu/abs/1999AJ....117.1616P>.
- E.F Helin, S.H. Pravdo, D.L. Rabinowitz, K.J. Lawrence, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 6, "Near-Earth Asteroid Tracking (NEAT) Program." See: <adsabs.harvard.edu/abs/1997NYASA.822....6H>.
See also:  <neat.jpl.nasa.gov>, <www.globalsecurity.org/space/systems/geodss.htm>.

W.F. Bottke, M.C. Nolan, H.J. Melosh, 1996, in: T.W. Rettig & J.M. Hahn (eds.), Completing the inventory of the Solar System, Astronomical Society of the Pacific Conference Proceedings, 107, 3, "Provenance of the Spacewatch Small Earth--Approaching Asteroids." See: <adsabs.harvard.edu/abs/1996ASPC..107....3B>.

V. Clube, B. Napier, 1996, Catastrophes and comets. The destroyers of cosmic faith, (Singapore: World Scientific). See: <adsabs.harvard.edu/abs/1996ccdc.book.....C>.

D.W. Cox, J.H. Chestek, 1996, Doomsday asteroid: can we survive? (Amherst, NY: Prometheus Books). See: <adsabs.harvard.edu/abs/1996QB377.C69......>.

P. Farinella, 1996, Meteorite, 2, 8, "Chaotic routes between the asteroid belt and Earth." See: <adsabs.harvard.edu/abs/1996Met.....2....8F>.

S. Hawking, 1996, Life in the Universe. See: <hawking.org.uk/index.php?option=com_content&view=article&id=65>.

G.L. Verschuur, 1996, Impact! The Threat of Comets and Asteroids (Oxford: OUP). See: <adsabs.harvard.edu/abs/1996itca.book.....V>.

T.H. Burbine, R.P. Binzel, S.J. Bus, J.M. Sunshine, 1996, Meteoritics & Planetary Science, 31, A24, "Spectroscopy of Near-Earth Asteroids: new results." See: <adsabs.harvard.edu/abs/1996M%26PSA..31R..24B>.

Fifth United Nations/European Space Agency Workshop on Basic Space Science: From Small Telescopes to Space Missions, hosted by the Arthur C. Clarke Center for Modern Technology on behalf of the Government of Sri Lanka, Colombo, Sri Lanka. Report (A/AC.105/640, 14 May 1996) resolves that an international network of telescopes under UN aegis is needed for NEO searching and tracking. See: <www.oosa.unvienna.org/pdf/reports/ac105/AC105_640E.pdf>.

S.V.M. Clube, 1996, Earth, Moon and Planets, 72, 433, "Evolution, punctuational crises and the threat to civilization." See: <adsabs.harvard.edu/abs/1996EM%26P...72..433C>.

T. Gehrels, R. Jedicke, 1996, Earth, Moon, and Planets, 72, 233, "The population of near-Earth objects discovered by Spacewatch." See: <adsabs.harvard.edu/abs/1996EM%26P...72..233G>.
See also: <spacewatch.lpl.arizona.edu/>.

R.A.F. Grieve, L.J. Pesonen, 1996, Earth, Moon and Planets, 72, 357, "Terrestrial impact craters: their spatial and temporal distribution and impacting bodies." See: <adsabs.harvard.edu/abs/1996EM%26P...72..357G>.

R. Jedicke, 1996, Astronomical Journal, 111, 970, "Detection of Near Earth Asteroids based upon their rates of motion." See: <adsabs.harvard.edu/abs/1996AJ....111..970J>.

M. Menichella, P. Paolicchi, P. Farinella, 1996, Earth, Moon and Planets, 72, 133, "The Main Belt as a source of Near-Earth Asteroids." See: <adsabs.harvard.edu/abs/1996EM%26P...72..133M>.

P. Michel, Ch. Froeschlé, P. Farinella, 1996, Earth, Moon, and Planets, 72, 151, "Dynamical evolution of NEAs: close encounters, secular perturbations and resonances." See: <adsabs.harvard.edu/abs/1996EM%26P...72..151M>.

J. Remo, 1996, Space Policy, 12, 13, "Policy perspectives from the UN international conference on near-Earth objects." See: <www.sciencedirect.com/science/article/pii/0265964695000348>.

Launch of NASA spacecraft Near Earth Asteroid Rendezvous – Shoemaker (NEAR – Shoemaker), a mission to rendezvous with near-Earth asteroid 433 Eros (1898 DQ, H = 11.16 mag, D = 34.4 × 11.2× 11.2 km, orbital P = 1.76 yr) on 12 February 2001. See: <near.jhuapl.edu/media/NEAR_fact_sheet.pdf>.

M. Boslough, 1996, Skeptical Inquirer, Vol. 20.2, March/April 1996, "Scientific knowledge is money in the bank." See: <www.csicop.org/si/show/scientific_knowledge_is_money_in_the_bank>.

T. Gehrels, 1996, Scientific American, 274, 34, "Collisions with comets and asteroids." See: <adsabs.harvard.edu/abs/1996SciAm.274c..34G>.

I. Halliday, A.A. Griffin, A.T. Blackwell, 1996, Meteoritics and Planetary Science, 31, 185, "Detailed data for 259 fireballs from the Canadian camera network and inferences concerning the influx of large meteoroids." See: <adsabs.harvard.edu/abs/1996M%26PS...31..185H>.

A.W. Harris, 1996, Lunar and Planetary Institute Science Conference Abstracts, 27, 493, "The rotation rates of very small asteroids: evidence for 'Rubble Pile' structure." See: <adsabs.harvard.edu/abs/1996LPI....27..493H>.

J.C. Solem, J.G. Hills, 1996, Astronomical Journal, 111, 1382, "Shaping of Earth-crossing asteroids by tidal forces." See: <adsabs.harvard.edu/abs/1996AJ....111.1382S>.

C. Koeberl, C.W. Poag, W.U. Reimold, D. Brandt, 1996, Science, 271, 1263, "Impact origin of the Chesapeake Bay structure and the source of the North American tektites." See: <adsabs.harvard.edu/abs/1996Sci...271.1263K>.

1996, Mar 20

Presentation by Adriane C. Ocampo at the 27^th Annual Lunar and Planetary Science Conference, 18-22 March 1996 in Houston (TX, USA) on a chain of impact craters in Chad suggested by space-borne radar images, possibly caused by a large, fragmented comet or asteroid similar to the Shoemaker-Levy 9 comet that slammed into Jupiter in 1994. The craters were discovered in radar images of the Earth taken by the Spaceborne Imaging Radar C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) that flew on the Space Shuttle Endeavour in April and October of 1994.
Ref:
-  A.C. Campo, K.O., Pope, 1996, Lunar and Planetary Science, 27, 977, "Shuttle Imaging Radar (SIR-C) images reveal multiple impact craters at Aorounga, Northern Chad." See: <adsabs.harvard.edu/abs/1996LPI....27..977O>,  <impact.arc.nasa.gov/news_detail.cfm?ID=81>.

1996, Mar 20

Parliamentary Assembly of the Council of Europe (Strasbourg, France), Resolution 1080: "On the detection of asteroids and comets potentially dangerous to mankind",  invited governments of member states and the European Space Agency (ESA) to give the necessary support to an international program to detect NEOs that are potentially dangerous to mankind and to develop a strategy for remedies against possible impacts. See: <www.cfa.harvard.edu/~marsden/SGF/resol.html>, <impact.arc.nasa.gov/news_detail.cfm?ID=82>.

1996, Mar 26

Inauguration of the Spaceguard Foundation (SGF), Rome, Italy, founded by E. Shoemaker, D. Steel, A. Carussi and the IAU WG-NEO. The SGF is currently located at the ESA Centre for Earth Observations (ESRIN) in Frascati (Italy). See: <spaceguard.iasf-roma.inaf.it/SGF/history.html>, <www.cfa.harvard.edu/~marsden/SGF/>, <spaceguard.esa.int>.

T. Gehrels, 1996, The Observatory, 116, 104, " Dinosauritis." See: <adsabs.harvard.edu/abs/1996Obs...116..104G>.

P. Michel, P. Farinella, Ch. Froeschlé, 1996, Nature, 380, 689, "The orbital evolution of the asteroid Eros and implications for collision with the Earth." See: <adsabs.harvard.edu/abs/1996Natur.380..689M>.

1996, May 14

Massive asteroid 1996 JA1 (H = 21.0 mag, D ≈ 200 m, PHA) discovered by Timothy B. Spahr on photographic plates at the University of Arizona.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1996+JA1+&orb=1>.
Ref:
-  T. Spahr, D.J. Tholen, M. Hicks, J. Collins, 1996, IAU Circ. 6402, "1996 JA1." See: <adsabs.harvard.edu/abs/1996IAUC.6402....1S>.
-  T.B. Spahr, C.W. Hergenrother, S.M. Larson, et al., 1997, Icarus, 129, 415, "The discovery and physical characteristics of 1996 JA1." See: <adsabs.harvard.edu/abs/1997Icar..129..415S>.
See also: <findarticles.com/p/articles/mi_m1200/is_n23_v149/ai_18385352/>, <en.wikipedia.org/wiki/Timothy_B._Spahr>.

1996, May 19

Asteroid 1996 JA1 (H = 21.0 mag, D ≈ 200 m, PHA) passed Earth at a nominal miss distance of 1.2 LD. Minimum miss distance 1.2 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1996+JA1+&orb=1>.

N.W. Harris, M.E. Bailey, 1996, Irish Astronomical Journal, 1996, 23(2), 151, "The cometary component of the Near-Earth Object population." See: <adsabs.harvard.edu/abs/1996IrAJ...23..151H>.

1996, Jul 8-12

International conference on Asteroids, Comets, Meteors, VI, Versailles (France). Proc.: A.V. Levasseur-Regourd & M. Fulchignoni (eds.), Asteroids, Comets, Meteors 1996, I: 1996, Planetary and Space Science, 45, No. 5; II: 1997, Planetary and Space Science, 45, No.7; III: 1997, Planetary and Space Science, 45, No.12; Planetary and Space Science, 46, No.8. See: <adsabs.harvard.edu/abs/1997P%26SS...45.....L>, <adsabs.harvard.edu/abs/1998P%26SS...46..835L>.

1996, Jul 15-17

International conference Tunguska '96, Bologna (Italy). See: <impact.arc.nasa.gov/news_detail.cfm?ID=88>.

T. Mallon, 8 July 1996, New York Times Magazine, "The asteroids are coming! The asteroids are coming! See: <www.nytimes.com/1996/07/28/magazine/the-asteroids-are-coming-the-asteroids-are-coming.html?pagewanted=all&src=pm>.

W.F. Bottke, M.C. Nolan, H.J. Melosh, 1996, Icarus, 122, 406, "Origin of the Spacewatch small Earth-approaching asteroids." See: <adsabs.harvard.edu/abs/1996Icar..122..406B>.

R.P. Binzel, S.J. Bus, Th.H. Burbine, J.M. Sunshine, 1996, Science, 273, 946, "Spectral properties of Near-Earth Asteroids: evidence for sources of ordinary chondrite meteorites." See: <adsabs.harvard.edu/abs/1996Sci...273..946B>.

P. Michel, C. Froeschle, P. Farinella, 1996, Astronomy & Astrophysics, 313, 993, "Dynamical evolution of two near-Earth asteroids to be explored by spacecraft: (433) Eros and (4660) Nereus." See: <adsabs.harvard.edu/abs/1996A%26A...313..993M>.

1996, Sep 23-27

2^nd  International Conference on Space Protection of the Earth (SPE-96), Snezhinsk/Chelyabinsk, Russian Federation. See: <impact.arc.nasa.gov/news_detail.cfm?ID=87>.

P.M. Sforza, J.L. Remo, 1996, Acta Astronautica, "Propulsion options for missions to near-Earth objects." See: <www.sciencedirect.com/science/article/pii/S009457659785432X>.

J.M. Urias, I.M. DeAngelis, D.A. Ahern, et al., 1996, paper presented to Air Force 2025, "Planetary Defense: catastrophic health insurance for planet Earth." See: <csat.au.af.mil/2025/volume3/vol3ch16.pdf >.

Start of the OCA-DLR Asteroid Survey (O.D.A.S.), to search for asteroids and comets with emphasis on NEO's, operated from October 1996 to April 1999 by the Observatoire de Côte d'Azur (OCA, Nice, France) and the DLR – Institute of Planetary Research (Berlin-Adlershof, Germany), in the framework of the EUNEASO project. Five NEAs were discovered. See: <earn.dlr.de/odas/>, <earn.dlr.de/euneaso.htm>.

Asteroid 2012 TC4 (H = 26.5 mag, D ≈ 20 m) passed Earth at a nominal miss distance of 0.015 LD (= 0.9 R_Earth from the geocenter). Minimum miss distance 0.003 LD (= 0.2 R_Earth from the geocenter).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012+UE34&orb=1>.
See also: 12 October 2012, 12 October 2017. 

The Japanese Spaceguard Association (JSGA)  officially founded. Plans for the future involved two 1-m class ground-based NEO telescopes in Japan and a 30-cm NEO telescope on the Moon. A 1-m wide-field telescope for NEO detection became operational in 2002, and observes NEOs down to v = 20.5 since 2006.
Ref:
- SGF Information Bulletin No. 1997/01, May 22, 1997, Item 7.
See also: <www.unoosa.org/pdf/reports/ac105/AC105_976E.pdf>, <www.oosa.unvienna.org/pdf/reports/ac105/C1/AC105_C1_100E.pdf >.

1996, Oct 21

Space Shield Foundation established in Russia. See: <impact.arc.nasa.gov/news_detail.cfm?ID=91>.

A.W. Harris, 1996, Mercury, 25, no.6, p.12, "Can we defend Earth against impacts by comets and small asteroids?" See: <adsabs.harvard.edu/abs/1996Mercu..25f..12H>.

1996, Nov 12

Founding of  Spaceguard UK, set up to promote UK NEO activities. The UK Spaceguard Centre is located at Knighton (Powys, Wales, UK). See: <www.spaceguarduk.com/>, <www.oosa.unvienna.org/pdf/reports/ac105/AC105_863Add1E.pdf>.

1996, Nov 22

Honduras bolide. Fireball over San Luis, Honduras. Estimated initial diameter D  ≈ 2 m. No meteorites were recovered.
Ref:
- NN, 1997, Sky & Telescope, 93, 12, "A hit in Honduras?";
- J. Borovička, C.M. Pineda de Carías, A. Ocampo, et al., 1999, in: W.J. Baggaley & V. Porubcan (eds.),  Meteoroids 1998, Proc. Int. Conf., Tatranska Lomnica (Slovakia), 17-21 August 1998 (Slovak Academy of Sciences: Astronomical Institute), "About a big fireball seen in Honduras." See: <adsabs.harvard.edu/abs/1999md98.conf..139B>, <impact.arc.nasa.gov/news_detail.cfm?ID=69>.

Asteroid 4179 Toutatis (1989 AC, H = 15.3 mag, D = 4.6×2.4×1.9 km, orbital P = 4.03 yr, PHA) passed Earth at 13.8 LD. It is the largest known PHA.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1989+AC+&orb=1>, <en.wikipedia.org/wiki/4179_Toutatis>.

A. Tollman, 1996, Astronomie + Raumfahrt in Unterricht, 33 (6), 12, "Ein Komet – Ursache der Sintflut." See: <www.fachportal-paedagogik.de/fis_bildung/suche/fis_set.html?FId=405749>.

1997

The survey project Lincoln NEA Research (LINEAR),  a MIT Lincoln Laboratory program funded by the US Air Force and NASA,  began operations with robotic telescopes and fast read-out CCD. Two LINEAR 1-m telescopes (White Sands Missile Range, Socorro, NM, USA) observe the sky five times per night. A third telescope is used for confirmation of NEO orbits, down to v = 20 mag. As of 31 December 2007, LINEAR had detected 2019 NEAs and 236 comets.
Ref:
-  G.H. Stokes, J.B. Evans, H.E.M. Viggh, et al., 2000, Icarus, 148, 21, "Lincoln NEA Research (LINEAR)." See: <adsabs.harvard.edu/abs/2000Icar..148...21S>;
- D.K. Yeomans, S.R. Chesley, P.W. Chodas, 2010, in: A.M. Finkelstein, W.F. Huebner & V.A. Shor (eds.), Proc. Intern. Conf. Asteroid-Comet Hazard 2009, Protecting the Earth against collisions with asteroids and comet nuclei, St. Petersburg (Russian Federation), 21-25 September 2009 (Saint Petersburg: Nauka), p. 244, "NASA's Near-Earth Object Program Office."
See also: <www.ll.mit.edu/mission/space/linear/>, <ftp://quasar.ipa.nw.ru/pub/ACHBOOK_2009/ach-2009_book.pdf >.

Spanish Meteor and Fireball Network. Operations started in 2004 using high-resolution all-sky CCD camera's and video systems at stations (25 by 2010) located around the Mediterranean coast.
Ref:
-  J.M. Trigo-Rodríguez, A.J. Castro-Tirado, J. Llorca, et al., 2004, Earth, Moon, and Planets, 95, 553, "The development of the  Spanish Fireball Network using a new all-sky CCD system." See: <adsabs.harvard.edu/abs/2004EM%26P...95..553T>;
- J.M. Trigo-Rodríguez, J. Llorca, A.J. Castro-Tirado, et al., 2006, Astronomy & Geophysics, 47, 6.26, " The Spanish fireball network." See: <adsabs.harvard.edu/abs/2006A%26G....47f..26T>, <www.spmn.uji.es/ENG/presentation.html>, <onlinelibrary.wiley.com/doi/10.1111/j.1468-4004.2006.47626.x/pdf>.

W. Alvarez, 1997, T. rex and the Crater of Doom (Princeton: Princeton Univ. Press). See: <press.princeton.edu/titles/6029.html>, <adsabs.harvard.edu/abs/1997S%26T....94f..78A>.

A. Boattini, A. Carusi, 1997, Vistas in Astronomy, 41, 527, "Atens: importance among Near-Earth Asteroids and search strategies." See: <adsabs.harvard.edu/abs/1997VA.....41..527B>.

M.B. Gerrard, A.W. Barber, 1997, New York University Environmental Law Journal, 6, 1, "Asteroids and comets: U.S. and international law and the lowest-probability, highest consequence risk." See: <www1.law.nyu.edu/journals/envtllaw/issues/vol6/1/6nyuelj4.html>

J.S. Lewis, 1997, Rain of iron and ice: the very real threat of comet and asteroid bombardment (Reading, MA: Addison-Wesley Pub. Co.). See: <adsabs.harvard.edu/abs/1997S%26T....93a..64L>.

D. Morrison, 1997, in: Y. Terzian & E. Bilson (eds.), Carl Sagan's Universe (Cambridge: CUP), p. 75, "Impacts and life: living in a risky planetary system." See: <adsabs.harvard.edu/abs/1997csu..book...75M>.

J.G. Hills, M.P. Goda, 1997, Meteoritics & Planetary Science, 32, A60, "The largest mass of nickel-iron meteorites." See: <adsabs.harvard.edu/abs/1997M%26PSA..32R..60H>.

D.I. Steel, 1997, Irish Astronomical Journal, 1997, 24(1), 19, "Project Spaceguard: will humankind go the way of the dinosaurs?" See: <adsabs.harvard.edu/abs/1997IrAJ...24...19S>.

O. Hernius, C.-I. Lagerkvist, M. Lindgren, G. Tancredi, G.V. Williams, 1997, Astronomy & Astrophysics, 318, 631, "UESAC - the Uppsala-ESO survey of asteroids and comets." See: <adsabs.harvard.edu/abs/1997A%26A...318..631H>.

O.B. Toon, K. Zahnle, D. Morrison, et al., 1997, Reviews of Geophysics, 35, 41, "Environmental perturbations caused by the impacts of asteroids and comets." See: <adsabs.harvard.edu/abs/1997RvGeo..35...41T>, <www.agu.org/journals/ABS/1997/96RG03038.shtml>.

Juancheng Superbolide, a fireball occurring over Shandong Province (China). The fireball was observed by IR detectors in Earth orbit. The meteoroid was thoroughly fragmented, yielding >1000 individual pieces of more than 100 kg in total. Initial meteoroid mass 4000 - 9000 kg, and 130 - 170 cm in diameter.
Ref:
-  J.F. Wacker, A.R. Hildebrand, P. Brown, D. Crawford, M.B.E. Boslough, et al., 1998, Meteoritics & Planetary Science, 33, A160, "The Juancheng and El Paso superbolides of February 15 and October 9, 1997: pre-atmospheric meteoroid sizes." See: <adsabs.harvard.edu/abs/1998M%26PSA..33..160W>.

W.F. Bottke, D.C. Richardson, S.G. Love, 1997, Icarus, 126, 470, "Can tidal disruption of asteroids make crater chains on the Earth and Moon?" See: <adsabs.harvard.edu/abs/1997Icar..126..470B>.

J.S. Lewis, 1997, Rain of iron and ice: the very real threat of comet and asteroid bombardment (Helix Books). See: <en.wikipedia.org/wiki/John_S._Lewis>.

P. Spurný, 1997, Planetary and Space Science, 45, 541, "Exceptional fireballs photographed in central Europe during the period 1993-1996." See: <adsabs.harvard.edu/abs/1997P%26SS...45..541S>.

J.G. Hills, M.P. Goda, 1997, Planetary and Space Science, 45, 595, "Meteoroids captured into Earth orbit by grazing atmospheric encounters." See: <adsabs.harvard.edu/abs/1997P%26SS...45..595H>.

E.F Helin, S.H. Pravdo, D.L. Rabinowitz, K.J. Lawrence, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 6, "Near-Earth Asteroid Tracking (NEAT) Program." See: <adsabs.harvard.edu/abs/1997NYASA.822....6H>.

G. Hahn, S. Mottola, A. Erikson, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 27, "Meteoroid orbits: implications for Near-Earth Object search programs." See: <adsabs.harvard.edu/abs/1997NYASA.822...31S>.

D. Steel, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 31, "Meteoroid orbits: implications for Near-Earth Object search programs." See: <adsabs.harvard.edu/abs/1997NYASA.822...31S>.

B.G. Marsden, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 52, "Overview of orbits." See: <adsabs.harvard.edu/abs/1997NYASA.822...52M>.

Z. Ceplecha, C. Jacobs, C. Zaffery, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 145, "Correlation of ground- and space-based bolides." See: <adsabs.harvard.edu/abs/1997NYASA.822..145C>.

R.A.F. Grieve, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 319, "Target Earth: evidence for large-scale impact events." See: <adsabs.harvard.edu/abs/1997NYASA.822..319G>.

J.G. Hills, C.L. Mader, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects, United Nations Intern. Conf., Annals New York Academy of Sciences, 822, 381, "Tsunami produced by the impacts of small asteroids." See: <adsabs.harvard.edu/abs/1997NYASA.822..381H>.

O.B. Toon, K. Zahnle, D. Morrison, et al., 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 401, "Environmental perturbations caused by the impacts of asteroids and comets." See: <adsabs.harvard.edu/abs/1997NYASA.822..401T>.

G.H. Canavan, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 539, "Optimal detection of Near-Earth Object threats." See: <adsabs.harvard.edu/abs/1997NYASA.822..539C>.

R.P. Binzel, 1997, in: J.L. Remo (ed.), Near-Earth Objects, United Nations Intern. Conf., Annals New York Academy of Sciences, 822, 545, "A Near-Earth Object hazard index." See: <adsabs.harvard.edu/abs/1997NYASA.822..545B>.

T. Gehrels, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 603, "A proposal to the United Nations regarding the international discovery programs of Near-Earth Asteroids." See: <adsabs.harvard.edu/abs/1997NYASA.822..603G>.

A. Carusi, 1997, in: J.L. Remo (ed.), Proc. Near-Earth Objects: the United Nations International Conference, New York (NY, USA), 24-26 April 1995, Annals of the New York Academy of Sciences, 822, 606, "International efforts toward the Spaceguard System." See: <adsabs.harvard.edu/abs/1997NYASA.822..606C>.

D. Morrison, 1997, Skeptical Inquirer, Vol. 21.3, "Is the sky falling?" See: <www.csicop.org/si/show/is_the_sky_falling>.

E. Pierazzo, A.M. Vickery, H.J. Melosh, 1997, Icarus, 127, 408, "A re-evaluation of impact melt production." See: <adsabs.harvard.edu/abs/1997Icar..127..408P>.

Inauguration of the 1.8 m Spacewatch Telescope on Kitt Peak (AZ, USA). See: <spacewatch.lpl.arizona.edu/>.

1997, Jun 27

NASA spacecraft Near Earth Asteroid Rendezvous – Shoemaker (NEAR – Shoemaker) flew within 1200 km by asteroid  253 Mathilde (1949 OL1, H = 10.2 mag, D = 66 × 48 × 46 km, main-belt asteroid).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1949+OL1&orb=1>, <en.wikipedia.org/wiki/253_Mathilde>.
Ref:
- A.F. Cheng, 1997, Space Science reviews, 82, 3, "Near Earth Asteroid Rendezvous: mission overview." See: <adsabs.harvard.edu/abs/1997SSRv...82....3C>;
- A.F. Cheng, A.G. Santo, K.J. Heeres, et al., 1997, Journal of Geophysical Research, 102, E10, p. 23695, "Near-Earth Asteroid Rendezvous: mission overview." See: <adsabs.harvard.edu/abs/1997JGR...10223695C>;
- D.K. Yeomans, J.-P. Barriot, D.W. Dunham, et al., 1997, Science, 278, 2106, "Estimating the mass of asteroid 253 Mathilde from tracking data during the NEAR flyby." See: <adsabs.harvard.edu/abs/1997Sci...278.2106Y>;
- E. Asphaug, 2004, in:  M.J.S. Belton, et al. (eds.), Mitigation of Hazardous Comets and Asteroids (Cambridge: C: mission overviewUP), p. 66, "Interior structures for asteroids and cometary nuclei". See: <adsabs.harvard.edu/abs/2004mhca.conf...66A>.
See also: <near.jhuapl.edu/media/NEAR_fact_sheet.pdf>,<solarsystem.nasa.gov/missions/profile.cfm?MCode=NEAR>, <www.nasa.gov/pdf/474202main_Cheng_ExploreNOW.pdf>>, <www.scientificamerican.com/article.cfm?id=near-ing-mathilde>.

Z. Ceplecha, R.E. McCrosky, 1997, Meteoritics & Planetary Science, 32, A157, "Prairie Network fireballs: data on height, distance and brightness for each measured time-mark." See: <adsabs.harvard.edu/abs/1997M%26PSA..32..157C>.

R. Bottomley, R. Grieve, D. York, V. Masaitis, 1997, Nature, 388, 365, "The age of the Popigai impact event and its relation to events at the Eocene/Oligocene boundary." See: <adsabs.harvard.edu/abs/1997Natur.388..365B>.

D.A. Kring, 1997, Meteoritics & Planetary Science, 32, 517, "Air blast produced by the Meteor Crater impact event and a reconstruction of the affected environment." See: <adsabs.harvard.edu/abs/1997M%26PS...32..517K>.

B.J. Gladman, F. Migliorini, A. Morbidelli, V. Zappala, P. Michelle, et al., 1997, Science, 277, 197, "Dynamical lifetimes of objects injected into asteroid belt resonances." See: <adsabs.harvard.edu/abs/1997Sci...277..197G>.

Asteroid 2011 PU1 (H = 25.1 mag, D ≈ 35 m) passed Earth at a nominal miss distance of 1.4 LD. Minimum miss distance 0.4 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011+PU1&orb=1>.
See also: 24 July 2011. 

B.G. Marsden, 1997, Planetary and Space Science, 45, 1049, "Obituary – Eugene M. Shoemaker (1928 – 1997)." See: <adsabs.harvard.edu/abs/1997P%26SS...45.1049M>.

J.S. Lewis, 1997, Mining the sky: untold riches from the asteroids, comets, and planets (New York: Perseus Publishing). See: <en.wikipedia.org/wiki/John_S._Lewis>.

V. Zappalà, A. Cellino, M. di Martino, et al., 1997, Icarus, 129, 1, "Maria's family: physical structure and possible implications for the origin of giant NEAs." See: <adsabs.harvard.edu/abs/1997Icar..129....1Z>.

H.J. Melosh, E.V. Ryan, 1997, Icarus, 129, 562, "Asteroids: shattered but not dispersed." See: <adsabs.harvard.edu/abs/1997Icar..129..562M>.

1997, Oct 9

El Paso superbolide. A large fireball seen at daylight from Chihuahua (Mexico) moving north to detonate east of El Paso (TX, USA). Recorded by satellite systems, seismographs, infrasound arrays and numerous video and still photographers. The terminal disaggregation energy released corresponds to a body of ~2 m and total mass of M  ≈ 15,000 kg.
Ref:
-  J.F. Wacker, A.R. Hildebrand, P. Brown, D. Crawford, M.B.E. Boslough, et al., 1998, Meteoritics & Planetary Science, 33, A160, "The Juancheng and El Paso superbolides of February 15 and October 9, 1997: pre-atmospheric meteoroid sizes." See: <adsabs.harvard.edu/abs/1998M%26PSA..33..160W>, <impact.arc.nasa.gov/news_detail.cfm?ID=80>.

US Department of Defense Clementine II mission to test technologies for interception of asteroids has fallen victim to a line-item veto: US President Clinton deleted $30M in funding for Clementine II from the FY1998 budget. Clementine II was supposed to fly by asteroids 4179 Toutatis and 1986 JK in the year 2000 and possibly to deliver impact probes. See: <impact.arc.nasa.gov/news_detail.cfm?ID=74>.

J. Smit, 1997, Nature, 390, 340, "Extraterrestrial impacts: the big splash". Comments on Gersonde et al. (1997), see below. See: <www.nature.com/nature/journal/v390/n6658/full/390340b0.html>, <www.nature.com/nature/journal/v449/n7158/full/449001b.html>.

R. Gersonde, F.T. Kyte, U. Bleil, 1997, Nature, 390, 357, "Geological record and reconstruction of the late Pliocene impact of the Eltanin asteroid in the Southern Ocean." See: <adsabs.harvard.edu/abs/1997Natur.390..357G>.

C. de Jager, 2012, Zenit, 24, 520, "De dood van de dinosauriërs." See: <www.dekoepel.nl/zenit/dooddinos.html>.

P. Pravec, M. Wolf, L. Sarounova, et al., 1997, Icarus, 130, 275, "The Near-Earth Objects follow-up program." See: <adsabs.harvard.edu/abs/1997Icar..130..275P>.

D.L. Rabinowitz, 1997, Icarus, 127, 33, "Are main-belt asteroids a sufficient source for the Earth-approaching asteroids?" See: <adsabs.harvard.edu/abs/1997Icar..127...33R>.

D.L. Rabinowitz, 1997, Icarus, 130, 287, "Are main-belt asteroids a sufficient source for the Earth-approaching asteroids?" See: <adsabs.harvard.edu/abs/1997Icar..130..287R>.

D.I. Steel, 1997, Planetary and Space Science, 45, 1501, "The ABC of ACM: asteroids, Buffon and comets." See: <adsabs.harvard.edu/abs/1997P%26SS...45.1501S>.

1997, Dec 9

Greenland superbolide. Fireball seen at night 150 km south of Nuuk (Greenland), by ground- and satellite-based cameras. Estimated initial NEA mass M  ≈ 36,000 kg. No meteorites were recovered. See: <impact.arc.nasa.gov/news_detail.cfm?ID=80>, <goes.gsfc.nasa.gov/text/9712.greenland/9712.greenland.html>, <en.wikipedia.org/wiki/List_of_meteor_air_bursts>.
Ref:
-  H. Pedersen, R.E. Spalding, E. Tagliaferri, et al., 2001, Meteoritics & Planetary Science, 36, 549, "Greenland superbolide event of 1997 December 9."  See: <adsabs.harvard.edu/abs/2001M%26PS...36..549P>.

E. Asphaug, 1997, Science, 278, 2070, "New views of asteroids."
See: <www.sciencemag.org/content/278/5346/2070.short>, <adsabs.harvard.edu/abs/1997Sci...278.2070A>.

1998

First asteroid discovered by Lowell Observatory NEO Search (LONEOS), started by E.L.G. Bowell. The 0.6m telescope project, funded by NASA, was terminated at the end of February 2008. LONEOS discovered 288 NEOs.

T. Gehrels, 1998, Meteorite, 4, 18, "Detection of asteroids." See: <adsabs.harvard.edu/abs/1998Met.....4Q..18G>.

T. Gehrels, 1998, Meteorite, 4, 18, "Detection of asteroids, Part 2." See: <adsabs.harvard.edu/abs/1998Met.....4R..18G>.

J.G. Hills, M.P. Goda, 1998, Science of Tsunami Hazards, 16, 3, "Tsunami from asteroid and comet impacts: the vulnerability of Europe." See: <library.lanl.gov/tsunami/00394718.pdf>.

C.L. Mader, 1998, Science of Tsunami Hazards, 16, 11, "Asteroid tsunami inundation of Japan." See: <library.lanl.gov/tsunami/00394718.pdf>.

C.L. Mader, 1998, Science of Tsunami Hazards, 16, 17, "Modeling the Eltanin asteroid tsunami." See: <library.lanl.gov/tsunami/00394718.pdf>.

D.A. Crawford, C.L. Mader, 1998, Science of Tsunami Hazards, 16, 21, "Modeling asteroid impact and tsunami." See: <library.lanl.gov/tsunami/00394718.pdf>.

J. Oberst, S. Molau, D. Heinlein, et al., 1998, Meteoritics & Planetary Science, 33, 49, "The 'European Fireball Network': current status and future prospects." See: <adsabs.harvard.edu/abs/1998M%26PS...33...49O>.

D.F. Lupishko, M. di Martino, 1998, Planetary and Space Science, 46, 47, "Physical properties of near-Earth asteroids." See: <adsabs.harvard.edu/abs/1998P%26SS...46...47L>.

D.P. Rubincam, 1998, Journal of Geophysical Research, 103, E1, 1725, "Yarkovsky thermal drag on small asteroids and Mars-Earth delivery." See: <adsabs.harvard.edu/abs/1998JGR...103.1725R>.

J.G. Hills, M.P. Goda, 1998, in: Proc. Intern. Workshop Tunguska 96, Planetary and Space Science, 46, 219, "Damage from the impacts of small asteroids." See: <adsabs.harvard.edu/abs/1998P%26SS...46..219H>.

A.W. Harris, 1998, Icarus, 131, 291, "A thermal model for Near-Earth Asteroids." See: <adsabs.harvard.edu/abs/1998Icar..131..291H>.

A.W. Harris, 1998, in: Proc. Intern. Workshop Tunguska 96, Planetary and Space Science, 46, 283, "Evaluation of ground-based optical surveys for near-Earth asteroids." See: <adsabs.harvard.edu/abs/1998P%26SS...46..283H>.

A. Montanari, A. Campo Bagatin, P. Farinella, 1998, in: Proceedings International Workshop Tunguska 96, Planetary and Space Science, 46, 271, "Earth cratering record and impact energy flux in the last 150 Ma." See: <adsabs.harvard.edu/abs/1998P%26SS...46..271M>.

K. Muinonen, 1998, in: Proceedings International Workshop Tunguska 96, Planetary and Space Science, 46, 291, "Discovery and follow-up simulations for small Earth-crossing asteroids." See: <adsabs.harvard.edu/abs/1998P%26SS...46..291M>.

Asteroid 1998 DK36 (H = 25.0 mag, D ≈ 35 m) passed Earth at a nominal miss distance of 4.4 LD. Minimum miss distance 0.2 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1998+DK36&orb=1>.

1998, Mar 11

B.G. Marsden, 1998, IAU Circular 6837, "1997 XF11." See: <www.cbat.eps.harvard.edu/iauc/06800/06837.html#Item2>.
IAU Circular 6837 contained the (later corrected) assertion of a possible impact on Earth by asteroid 1997 XF11 (H = 16.9 mag, D ≈ 1.5 km, PHA) on 26 Oct 2028. The ensuing debate over orbit determination, evaluation of impact risks and the dissemination of such results led to considerable activity. Improved analyses predicted an approach distance of 2.42 LD (929,000 km) on 26 Oct 2028.
Ref:
- B.G. Marsden, 1998, Boston Sunday Globe, 29 March 1989, "How the asteroid story hit: an astronomer reveals how a discovery spun out of control." See: <www.minorplanetcenter.net/iau/pressinfo/1997XF11Globe.html>;
-  I. Semeniuk, 1998, Mercury, 27, No. 6, p. 12, "Armageddon? … Sorry, just Armakiddin!" See: <adsabs.harvard.edu/abs/1998Mercu..27f..12S>;
-  B.G. Marsden, 1999, AAS-DAA meeting #31, #07.02, "Asteroid 1997 XF11 could collide with earth." See: <adsabs.harvard.edu/abs/1999DDA....31.0702M>;
- B.G. Marsden, 1999, Journal of the British Astronomical Association, 109, 39, "1997 XF11 - the true story." See: <adsabs.harvard.edu/abs/1999JBAA..109...39M>;
-  B.G. Marsden, 1999, Journal British Interplanetary Society, 52 (5 - 6), 195, "A discourse on 1997 XF11." See: <adsabs.harvard.edu/abs/1999JBIS...52..195M>;
-  D. Morrison, C.R. Chapman, D. Steel, R.P. Binzel, 2004, in: M.J.S. Belton, et al. (eds.), 2004, Mitigation of Hazardous Comets and Asteroids (Cambridge: CUP), p. 353, "Impacts and the public: communicating the nature of impact hazard." See: <adsabs.harvard.edu/abs/2004mhca.conf..353M>;
-  B.G. Marsden, 2007, in: P. Bobrowsky & H. Rickman (eds.), 2007, Comet/Asteroid Impacts and Human Society (Berlin: Springer), p. 505, "Impact risk communication management (1998 – 2004): Has it improved?" See: <adsabs.harvard.edu/abs/2007caih.book.....B>.
See also: <www.cfa.harvard.edu/iauc/06800/06837.html#Item2>, <impact.arc.nasa.gov/news_detail.cfm?ID=60>, <impact.arc.nasa.gov/news_detail.cfm?ID=63>, <sciencenow.sciencemag.org/cgi/content/full/1998/311/1>, <www.nytimes.com/1998/03/13/us/man-in-the-news-a-cheery-herald-of-fear-brian-geoffrey-marsden.html>, <discovermagazine.com/2000/oct/featblunders/>.

J.G. Spray, S.P. Kelley, D.B. Rowley, 1998, Nature, 392, 171, "Evidence for a late Triassic multiple impact event on Earth." See: <adsabs.harvard.edu/abs/1998Natur.392..171S>, <www.nature.com/nature/journal/v392/n6672/abs/392171a0.html>.
On the Manicouagan Crater, one of the oldest known impact craters, located in the Côte-Nord region of Québec, Canada, about 300 km north of the city of Baie-Comeau. See: <en.wikipedia.org/wiki/Manicouagan_crater>.

B.G. Marsden, 1998, Boston Sunday Globe, 29 March 1989, "How the asteroid story hit: an astronomer reveals how a discovery spun out of control." See: <www.minorplanetcenter.net/iau/pressinfo/1997XF11Globe.html>.

1998, Apr

The Catalina Sky Survey came into operation, starting from the ashes of an old photographic project started by Spahr & Hergenrother in 1993 (
Ref:
-  T.B. Spahr, C. Hergenrother, S.M. Larson, 1993, BAAS, 25, 1059). The CSS consists of a consortium of three cooperating surveys, all funded by NASA: the original Catalina Sky Survey (CSS, 0.7-m telescope) in Arizona, the Siding Spring Survey (SSS, 0.5-m telescope) in Australia, and the Mt. Lemmon Survey (MLSS, 1.5-m telescope) in Arizona. As of 2009, CSS had discovered more than 2,142 NEOs down to v = 22 mag.
Ref:
-  T.B. Spahr, C. Hergenrother, S.M. Larson, 1993, BAAS, 25, 1059, "High ecliptic latitude asteroid and comet search." See: <adsabs.harvard.edu/abs/1993DPS....25.1013S>;
-  D.K. Yeomans, S.R. Chesley, P.W. Chodas, 2010, in: A.M. Finkelstein, W.F. Huebner & V.A. Shor (eds.), Proc. Intern. Conf. Asteroid-Comet Hazard 2009, Protecting the Earth against collisions with asteroids and comet nuclei, St. Petersburg (Russian Federation), 21-25 September 2009 (Saint Petersburg: Nauka), p. 244, "NASA's Near-Earth Object Program Office."
- A.J. Drake, S.G. Djorgovski, A. Mahabal, et al., April 2012, in: R.E. Griffin, R.J. Hanisch, R.L. Seaman (eds.), New horizons in time-domain astronomy, Proceedings IAU Symposium No. 285 (Cambridge: CUP), 306, "The Catalina Real-time Transient Survey." See: <adsabs.harvard.edu/abs/2012IAUS..285..306D>.
See also: <www.lpl.arizona.edu/css/>, <uanews.org/node/23277>, <ftp://quasar.ipa.nw.ru/pub/ACHBOOK_2009/ach-2009_book.pdf>, <www.space.com/14911-dangerous-asteroids-search-nasa-funding.html>, <www.mso.anu.edu.au/~rmn/>, <www.newscientist.com/article/mg21528724.800-vital-eye-for-killer-asteroids-could-shut-imminently.html>, <www.canberratimes.com.au/national/funding-black-hole-means-our-asteroid-sentinel-may-abandon-crucial-work-20120710-21ubf.html>, <en.wikipedia.org/wiki/Catalina_Sky_Survey>.

P. Farinella, D. Vokroughlický, W.K. Hartmann, 1998, Icarus, 132, 378, "Meteorite delivery via Yarkovsky orbital drift." See: <adsabs.harvard.edu/abs/1998Icar..132..378F>.

D.I. Steel, 1998, Planetary and Space Science, 46, 473, "Distributions and moments of asteroid and comet impact speeds upon the Earth and Mars." See: <adsabs.harvard.edu/abs/1998P%26SS...46..473S>.

1998, May 21

U.S. Congressional Hearing on NEOs and Planetary Defense. Statement by Carl Pilcher, Science Director, Solar System Exploration, Office of Space Science, NASA, announcing the Spaceguard Goal to the U.S. House Subcommittee on Space & Aeronautics, i.e., find and track 90% of NEOs with D > 1 km. See: <impact.arc.nasa.gov/gov_asteroidperils_1.cfm>, <impact.arc.nasa.gov/gov_asteroidperils_3.cfm>.

1998, Jun

NASA Near Earth Orbit Program Office established at NASA Jet Propulsion Laboratory (Pasadena, CA, USA), to coordinate and provide a focal point for US studies of NEOs. See: <neo.jpl.nasa.gov/>,  <impact.arc.nasa.gov/programs_office.cfm>.

J. Borovička, O.P. Popova, I.V. Nemtchinov, P. Spurný, Z. Ceplecha, 1998, Astronomy & Astrophysics, 334, 713, "Bolides produced by impacts of large meteoroids into the Earth's atmosphere: comparison of theory with observations. I. Benešov bolide dynamics and fragmentation." See: <adsabs.harvard.edu/abs/1998A%26A...334..713B>.
-      Benešov bolide was detected and observed at the Czech stations of the European Fireball Network on 7 May 1991, one of the brightest and best-documented bolides.

G.L. Verschuur, 1998, Sky & Telescope, 95(6), 26, "Impact hazards: truth and consequences." See: <adsabs.harvard.edu/abs/1998S%26T....95f..26V>.

A.W. Harris, 1998, Nature, 393, 418, "Planetary science: making and braking asteroids." See: <adsabs.harvard.edu/abs/1998Natur.393..418H>.

E. Asphaug, S.J. Ostro, R.S. Hudson, D.J. Scheeres, W. Benz, 1998, Nature, 393, 437, "Disruption of kilometre-sized asteroids by energetic collisions." See: <adsabs.harvard.edu/abs/1998Natur.393..437A>.

Asteroid 1998 KY26 (H = 25.6 mag, D ≈ 30 m) passed Earth at a nominal miss distance of 2.1 LD. Minimum miss distance 2.1 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1998+KY26+&orb=1>, <en.wikipedia.org/wiki/1998_KY26>.
Ref:
-  S.J. Ostro, P. Pravec, L.A.M. Benner, et al. 1999, Science, 285, 557, "Radar and optical observations of asteroid 1998 KY26." See: <adsabs.harvard.edu/abs/1999Sci...285..557O>. 
See also: <antwrp.gsfc.nasa.gov/apod/ap020919.html>.

F. Langenhorst, G. Shafranovsky, V.L. Masaitis, 1998, Meteoritics & Planetary Science, 33, A90, "A comparative study of impact diamonds from the Popigai, Ries, Sudbury, and Lappajarvi Craters." See: <adsabs.harvard.edu/abs/1998M%26PSA..33R..90L>.

V. Zappalà, A.Cellino, B.J. Gladman, et al., 1998, Icarus, 134, 176, "Asteroid showers on Earth after family breakup events." See: <adsabs.harvard.edu/abs/1998M%26PSA..33R..90L>.

1998, Jul 4

The International Astronomical Union Executive Committee, at its 71^st meeting in Paris, on the initiative of General Secretary Johannes Andersen, issued a policy statement, which made clear that the detection and observations of NEOs to determine their orbits "is an international responsibility that requires the efforts of and support for astronomers around the world." It also stated that the IAU "coordinates this activity through the IAU Working Group on Near Earth Objects (WG-NEO) and offers the services of the Minor Planet Center, the international clearing house and data disseminator for NEO observations and research." It was emphasized that this was not a scientific policy judgment, but a policy issue related to public safety. See: <www.intastun.org/neo.html>.

1998, Aug

S.J. Ostro, C. Sagan, 1998, Astronomy & Geophysics, 39, 22, "Cosmic collisions and galactic civilizations." See: <adsabs.harvard.edu/abs/1998A%26G....39d..22O>.

A.W. Harris, 1998, in: J.A. Andersen (ed.), Proc. IAU  XXIII GA Joint Discussion Interactions between Planets and Small Bodies, in: Highlights in Astronomy, 11A, 257, "Searching for NEAs from Earth or space." See: <adsabs.harvard.edu/abs/1998HiA....11..257H>.

A.D. Taylor, W.G. Elford, 1998, in: J.A. Andersen (ed.), Proc. IAU XXIII GA Joint Discussion Interactions between Planets and Small Bodies, in: Highlights in Astronomy, 11A, 239, "Aspects of the terrestrial influx of small meteoroids." See: <adsabs.harvard.edu/abs/1998HiA....11..239T>.

Z. Ceplecha, J. Borovička, W.G. Elford, et al., 1998, Space Science Reviews, 84, 327, "Meteor phenomena and bodies." See: <adsabs.harvard.edu/abs/1998SSRv...84..327C>.

A. Morbidelli, B. Gladman, 1998, Meteoritics & Planetary Science, 33, 999, "Orbital and temporal distributions of meteorites originating in the asteroid belt." See: <adsabs.harvard.edu/abs/1998M%26PS...33..999M>.

R. Greenberg, 1998, Science, 281, 1971, "How asteroids come to Earth." See: <adsabs.harvard.edu/abs/1998Sci...281.1971G >.

F. Migliorini, P. Michel, A. Morbidelli, et al., 1998, Science, 281, 2022, "Origin of multi-kilometer Earth- and Mars-crossing asteroids: a quantitative simulation." See: <adsabs.harvard.edu/abs/1998Sci...281.2022M>.

R.B. Stothers, 1998, Monthly Notices Royal Astronomical Society, 300, 1098, "Galactic disc dark matter, terrestrial impact cratering and the law of large numbers." See: <adsabs.harvard.edu/abs/1998MNRAS.300.1098S>.

J.C. Wynn, E.M. Shoemaker, 1998, Scientific American, 279 (5), 36, "The day the sands caught fire." See: <adsabs.harvard.edu/abs/1998SciAm.279e..36W>, <volcanoes.usgs.gov/jwynn/1998SciAm-Wabar.pdf>.

Leonid meteor shower "Glowworm", seen over Kirtland Air Force Base, Albuquerque (NM, USA). See: <apod.nasa.gov/apod/ap000428.html>.

Leonid Fireball over Monteromano (Italy). See: <apod.nasa.gov/apod/ap991112.html>.

Leonid Fireball over Cape Canaveral (FL, USA). See: <apod.nasa.gov/apod/ap981120.html>.

Large Leonid meteor fireballs over northern New Mexico.
Ref:
-  J. Zinn, J. Wren, R. Whitaker, et al., 1999, Meteoritics & Planetary Science, 34, 1007, "Coordinated observations of two large Leonid meteor fireballs over northern New Mexico, and computer model comparisons." See: <adsabs.harvard.edu/abs/1999M%26PS...34.1007Z>.

E.M. Shoemaker, 1998, Journal of the Royal Astronomical Society of Canada, 92, 297, "Impact cratering through geologic time." See: <adsabs.harvard.edu/abs/1998JRASC..92..297S>.

NASA spacecraft Near Earth Asteroid Rendezvous – Shoemaker (NEAR – Shoemaker) arrives at asteroid 433 Eros (1898 DQ, H = 11.16 mag, D = 34.4 × 11.2× 11.2 km, orbital P = 1.76 yr, Amor asteroid). 
See: <near.jhuapl.edu/media/NEAR_fact_sheet.pdf>, <www.scientificamerican.com/article.cfm?id=come-closer-my-near>, <en.wikipedia.org/wiki/433_Eros>.

650 NEAs known, of which 166 PHAs. See: <neo.jpl.nasa.gov/stats/>.

1999

The 10,000^th minor planet was numbered at the IAU Minor Planet Center: main-belt asteroid 10000 Myriostos (1951 SY, H = 15.3 mag, D ≈ 3 km), discovered by Albert G. Wilson at Palomar Observatory (CA, USA).
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1951+SY&orb=1>, <en.wikipedia.org/wiki/10000_Myriostos>.
See also: <www.iau.org/static/publications/IB104.pdf>, p. 67, <www.physics.uc.edu/~sitko/AdvancedAstro/25-SmallBodies/SmallBodies.htm>.

1999

NASA NEO Program Office at Jet Propulsion Laboratory (Caltech, Pasadena, CA, USA) begins partial funding of the Minor Planet Center.

1999

LINEAR adds second co-located 1m search telescope with fast read-out CCD.

1999

Australian National Observatory 0.5 m telescope in Siding Spring begins  follow up observations as part of the Catalina Sky Survey. See: <www.lpl.arizona.edu/css/index.html>.

J.S. Lewis, 1999, Comet and asteroid impact hazards on a populated Earth (New York: Academic Press). See: <en.wikipedia.org/wiki/John_S._Lewis>, <adsabs.harvard.edu/abs/2000caih.book.....L>.

C.W. Poag, 1999, Chesapeake invader: discovering America's giant meteorite crater (Princeton: Princeton University Press). ISBN 0-691-00919-8

A. Morbidelli, 1999, Celestial Mechanics and Dynamical Astronomy, 73(1/4), 39, "Origin and evolution of Near Earth Asteroids." See: <adsabs.harvard.edu/abs/1999CeMDA..73...39M>.

Fireball over Czech Republic, recorded by the European Fireball Network. The luminous trail is measured to begin at an altitude of 81.9 kilometers and covered 71.1 kilometers in 6.7 seconds. See: <apod.nasa.gov/apod/ap990219.html>.

1999, Mar

The threat from NEOs is debated in the UK House of Commons. Minister for Energy & Industry, John Battle, said that the government will consult British astronomers and other experts on ways the UK can support NEO research.

1999, Mar 5-6

Near Earth Objects Dynamic Site (NEODyS) created, as an Italian/Spanish service that provides information on NEOs, operated at the University of Pisa (Italy), with a mirror site in Valladolid (Spain). Operational since November 1999. Both the University of Pisa and JPL post their web sites for information on NEOs (close approaches, ephemerides, orbital data). The close approach monitoring efforts, CLOMON at Pisa and SENTRY at NASA-JPL were initiated later. Since early 2002 the two automated NEO close approach monitoring services, CLOMON2 (Pisa) and SENTRY (JPL), are cross-checking their monitoring results.
Starting from 1 September 2011 NEODyS is sponsored by ESA, which pays a portion of the operating costs, both for the background orbit and risk computations and for the database and web interface; the rest of the cost is covered, as before, by the Department of Mathematics, University of Pisa, with the running research grants of the Celestial Mechanics Group, and by IASF-INAF (Rome), with a PRIN-INAF grant.
Ref:
-  A. Milani, S.R. Chesley, M.E. Sansaturio, G. Tommei, G.B. Valsecchi, 2005, Icarus, 173, 362, "Nonlinear impact monitoring: line of variation searches for impactors."
Ref:
-  A. Milani, S.R. Chesley, M.E. Sansaturio, G. Tommei, G.B. Valsecchi, Icarus, 173, 362, "Nonlinear impact monitoring: line of variation searches for impactors." See: <adsabs.harvard.edu/abs/2005Icar..173..362M>.
See also: <newton.dm.unipi.it/neodys/>, <adsabs.harvard.edu/abs/2001DPS....33.4108C>, <aas.org/archives/BAAS/v31n4/dps99/28.htm>, <en.wikipedia.org/wiki/NEODyS>.

D. Vokrouhlický, 1999, Astronomy & Astrophysics, 344, 362, "A complete linear model for the Yarkovsky thermal force on spherical asteroid fragments." See: <adsabs.harvard.edu/abs/1999A%26A...344..362V>.

1999, May

NASA/USAF NEO Search Program. NASA, in collaboration with the USA Air Force, is moving to implement a search program to meet the objectives of the Spaceguard Survey, as set down in the NASA Spaceguard reports of 1992 and 1995. See: <impact.arc.nasa.gov/news_detail.cfm?ID=22>.

1999, May

In a report to the ESA Council at ministerial level, the ESA Long-Term Space Policy Committee recommended (Action 13, Threat of  Cosmic Collision) that ESA be involved in NEO activities, including the study of counter measures.
Ref:
-  LSPC Report "Investing in Space – the Challenge for Europe", 1999, ESA SP-2000. See: <www.esa.int/esapub/sp/sp2000/sp2000.pdf>.

A. Poveda, M.A. Herrera, J.L. García, K. Curioka, 1999, Planetary and Space Science, 47, 679, "The diameter distribution of Earth-crossing asteroids." See: <adsabs.harvard.edu/abs/1999P%26SS...47..679P>.

A. Poveda, M.A. Herrera, J.L. García, A. Hernandéz-Alcántara, K. Curioka, 1999, Planetary and Space Science, 47, 715, "The expected frequency of collisions of small meteorites with cars and aircraft." See: <adsabs.harvard.edu/abs/1999P%26SS...47..715P>.

1999, May 6

Asteroid 2000 SG344 (H = 24.8 mag, D ≈ 37 m) passed Earth at a nominal miss distance of 1.5 LD. Minimum miss distance 1.5 LD.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2000+SG344&orb=1>, <en.wikipedia.org/wiki/2000_SG344>.
See also: 7 May 2028. 
Ref:
-  D. Morrison, C.R. Chapman, D. Steel, R.P. Binzel, 2004, in: M.J.S. Belton, et al. (eds.), 2004, Mitigation of Hazardous Comets and Asteroids (Cambridge: CUP), p. 353, "Impacts and the public: communicating the nature of impact hazard." See: <adsabs.harvard.edu/abs/2004mhca.conf..353M>;
-  B.G. Marsden, 2007, in: P. Bobrowsky & H. Rickman (eds.), 2007, Comet/Asteroid Impacts and Human Society (Berlin: Springer), p. 505, "Impact risk communication management (1998 – 2004): Has it improved?" See: <adsabs.harvard.edu/abs/2007caih.book.....B>.

R.P. Binzel, M. A'Hearn, C.R. Chapman, C. Chyba, A.L. Cochran, A.W. Harris, D.K. Yeomans, B.G. Marsden, R.L. Millis & D. Morrison, 1999, "From the pragmatic to the fundamental: the scientific case for near-Earth object surveys." Report prepared for the Astronomy and Astrophysics Survey Committee (AASC) of the National Academy of Sciences. See:

A. Milani, S.R. Chesley, G.B. Valsecchi, 1999, Astronomy & Astrophysics (Letters), 346, L65, "Close approaches of asteroid 1999 AN10: resonant and non-resonant returns." See: <adsabs.harvard.edu/abs/1999A%26A...346L..65M>.
See also:     7 August 1927.

A. Morbidelli, D. Nesvorný, 1999, Icarus, 139, 295, "Numerous weak resonances drive asteroids toward terrestrial planets orbits." See: <adsabs.harvard.edu/abs/1999A%26A...346L..65M>.

1999, Jun

Threat from NEOs discussed in UK House of Lords. Science Minister, Lord Sainsbury, says that Britain must cooperate internationally on this topic. See: <www.greatdreams.com/near.htm>.

1999, Jun 1-4

Torino Workshop on International Monitoring Programs for Asteroid and Comet Threat (IMPACT), Torino (Italy), organized by IAU Commission 15, the Spaceguard Foundation and others, and co-sponsored by NASA, ESA, IAU, ASI, IACG, Planetary Society, Alenia. The outcome includes the "Torino Scale" (describing risk and severity of possible impact for newly discovered hazardous objects), a call for national Spaceguard centres, and a plea to finance these centers in order to facilitate international collaboration in the international Spaceguard programme.
Ref:
-  R.P. Binzel, 2000, Planetary and Space Science, 48, 297, "The Torino Impact Hazard Scale." See: <adsabs.harvard.edu/abs/2000P%26SS...48..297B>.
See also: <impact.arc.nasa.gov/news_detail.cfm?ID=49>, <impact.arc.nasa.gov/news_detail.cfm?ID=55>,
<impact.arc.nasa.gov/news_detail.cfm?ID=35>,
<neo.jpl.nasa.gov/news/news024.html>.

The Torino Impact Hazard Scale announced simultaneously by the IAU and by NASA.
Ref:
-  D. Morrison, C.R. Chapman, D. Steel, R.P. Binzel, 2004, in: M.J.S. Belton, et al. (eds.), 2004, Mitigation of Hazardous Comets and Asteroids (Cambridge: CUP), p. 353, "Impacts and the public: communicating the nature of impact hazard." See: <adsabs.harvard.edu/abs/2004mhca.conf..353M>, <neo.jpl.nasa.gov/torino_scale.html>.

1999, Jul

The Third United Nations Conference on the Exploration and Peaceful Uses of Outer Space (UNISPACE III, Vienna, Austria), held a workshop on NEOs and made recommendations to the UN General Assembly. Resolution 1 adopted by the Conference, the Vienna Declaration on Space and Human Development, declares a strategy including actions that should be taken to: improve knowledge of NEOs; improve international coordination of activities related to NEOs; harmonize worldwide effort directed to identification, follow-up observations and orbit prediction; and research safety measures on the use of nuclear power sources in outer space.
The Vienna Declaration stated that:
– That the United Nations take the initiative of inviting all Member States to support near-Earth object research in their own countries, through the establishment of national or regional “spaceguard” centres to be coordinated by the international Spaceguard Foundation;
– That every effort be made to provide financial support for near-Earth object research, both theoretical and observational (from ground and space), …
– The United Nations support and promote greater involvement of scientists and observatories from nations in the southern hemisphere, ...
This Vienna Declaration was endorsed by the UN General Assembly in December 1999. In 2001, in response to recommendation 14 of UNISPACE III, Action Team 14 on NEOs was established by UN-COPUOS with terms of reference: (a) review the content, structure and organization of on-going efforts in the field of NEOs; (b) identify any gaps in the on-going work where additional cooperation is required and/or where other countries or organizations could make contributions; and (c) propose steps for the improvement of international coordination in collaboration with specialized bodies. See: <www.oosa.unvienna.org/oosa/unisp-3/index.html>.

Start of the Arcetri NEO Precovery Program (ANEOPP). See: <www.arcetri.astro.it/science/aneopp/>.
Ref:
- A. Boattini, G. D'Abramo, G. Forti, R. Gal, 2001, Astronomy & Astrophysics, 375, 293, "The Arcetri NEO Precovery Program." See: <adsabs.harvard.edu/abs/2001A%26A...375..293B>; 
- A. Boattini, G. D'Abramo, G. Forti, 2003, Memorie della Società Astronomica Italiana, 74, 864, "The importance of Near Earth Object detections on archival images: recent results and future potential." See: <adsabs.harvard.edu/abs/2003MmSAI..74..864B>.

W.K. Hartmann, P. Farinella, D. Vokrouhlický, 1999, Meteoritics & Planetary Science, 34, A161, "Reviewing the Yarkovsky effect: new light on the delivery of stone and iron meteorites from the asteroid belt." See: <adsabs.harvard.edu/abs/1999A%26A...347..711M>.

P. Michel, R. Gonczi, P. Farinella, 1999, Astronomy & Astrophysics, 347, 711, "Dynamical evolution of 1036 Ganymed, the largest near-Earth asteroid." See: <adsabs.harvard.edu/abs/1999M%26PSA..34..161H>.

1999, Jul 26-30

International conference on Asteroids, Comets, Meteors, VII, Cornell University, Ithaca (NY, USA). See: <impact.arc.nasa.gov/news_detail.cfm?ID=52>.

1999, Jul 29

NASA spacecraft Deep Space 1 (1998 – 2001) flew by NEA 9969 Braille (1992 KD, H = 15.8 mag, D ≈ 2.5 km, PHA, Mars-crossing asteroid) at a distance of 26 km.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1992+KD&orb=1>, <en.wikipedia.org/wiki/9969_Braille>.
Ref:
-  B.J. Buratti, D.T. Britt, L.A. Soderblom, et al., 2004, Icarus, 167, 129, "9969 Braille: Deep Space 1 infrared spectroscopy, geometric albedo and classification." See: <adsabs.harvard.edu/abs/2004Icar..167..129B>.
See also: <nmp.nasa.gov/ds1/gen/gen3.html>, <impact.arc.nasa.gov/news_detail.cfm?ID=53>,  <antwrp.gsfc.nasa.gov/apod/ap990805.html>.

1999 AAS/AIAA Astrodynamics Specialist Conference, Girdwood, Alaska (USA). See: <www.space-flight.org/AAS_meetings/1999_astro/1999_astro.html>.

P.W. Chodas, D.K. Yeomans, 1999, presented at the 1999 AAS/AIAA Astrodynamics Specialist Conference, Girdwood, Alaska (USA), 15-19 August 1999, "Predicting close approaches and estimating impact probabilities for Near-Earth Objects." See: <md1.csa.com/partners/viewrecord.php?requester=gs&collection=TRD&recid=A0035184AH&q=&uid=790941543&setcookie=yes>.
See also: <www.space-flight.org/AAS_meetings/1999_astro/1999_astro.html>.

C.R. Chapman, 1999, case study for Workshop on prediction in the Earth sciences: use and misuse in policy making, 10-12 July 1997, National Center for Atmospheric Research, Boulder (CO, USA) and 10-12 September 1998, Estes Park (CO, USA), "The asteroid/comet impact hazard." See: <www.boulder.swri.edu/clark/ncar799.html>.

A. Boattini, G. D'Abramo, G.B. Valsecchi, 1999, Bulletin American Astronomical Society, 31, 1117, #28.07, "NEO follow-up coordination using the Spaceguard Central Node: priority list and opportunties." See: <adsabs.harvard.edu/abs/1999BAAS...31.1117B>.

1999, Sep

Start of UAO – DLR Asteroid Survey (UDAS), a collaboration between the Uppsala Astronomical Observatory (UOA, 1 m Schmidt, Uppsala, Sweden) and the Deutschen Zentrum für Luft- und Raumfahrt (DLR, the German Aerospace Center, Berlin, Germany). From 1999 to 2011 a number of 215 asteroids have been detected. See: <earn.dlr.de/udas>, <en.wikipedia.org/wiki/UAO-DLR_Asteroid_Survey>.

J.G. Hills, M.P. Goda, 1999, Physica D: Nonlinear Phenomena, 133, 189, "Damage from comet-asteroid impacts with Earth." See: <adsabs.harvard.edu/abs/1999PhyD..133..189H>.

Asteroid 101955 (1999 RQ36, H = 20.8 mag, D ≈ 575 m, PHA) passed Earth at 5.7 LD. This asteroid will approach Earth closely again (1.7 LD) on 23 September 2060.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1999+RQ36&orb=1>.
Ref:
- S.R. Chesley, M.C. Nolan, D. Farnocchia, et al., May 2012, in: American Astronomical Society, DDA meeting #43, #7.08, "The trajectory dynamics of Near-Earth Asteroid 101955 (1999 RQ36)." See: <adsabs.harvard.edu/abs/2012DDA....43.0708C>.
See also: <www.jpl.nasa.gov/asteroidwatch/newsfeatures.cfm?release=2012-145>, <en.wikipedia.org/wiki/1999_RQ36>.

T. Gehrels, E. Echternach, 1999, Zenit, 26(10), 416, "Mooi, maar gevaarlijk: de dodelijke schoonheid van kometen en planetoiden." See: <adsabs.harvard.edu/abs/1999Zenit..26..416G>.

J.S. Lewis, 1999, Comet and asteroid impact hazards on a populated earth: computer modeling (Waltham: Academic Press). See: <en.wikipedia.org/wiki/John_S._Lewis>.

S. Isobe, 1999, Advances in Space Research, 23(11), 1861, "Proposed lunar-based telescopes for NEO observations." See: <adsabs.harvard.edu/abs/1999AdSpR..23.1861I>.

E. Asphaug, 1999, Nature, 402, 127, "Survival of the weakest." See: <adsabs.harvard.edu/abs/1999Natur.402..127A>.

W. Benz, E. Asphaug, Icarus, 142, 5, "Catastrophic disruptions revisited." See: <adsabs.harvard.edu/abs/1999Icar..142....5B>.

T. Gehrels, 1999, Earth, Planets and Space, 51, 1155, "A review of comet and asteroid statistics." See: <adsabs.harvard.edu/abs/1999EP%26S...51.1155G>.

First-ever radar images of a main-belt asteroid: 216 Kleopatra (H = 7.30 mag, D = 270 × 94 × 81 km) obtained with the 305 m Arecibo radio telescope by Steven J. Ostro (1946 – 2008) of NASA JPL, Pasadena (CA, USA). Shape: dog bone. At the time of observation the distance to 216 Kleopatra was d = 171 × 10⁶ km. As of May 2008, Ostro and his collaborators had detected 222 NEAs (including 130 PHAs and 24 binaries) and 118 main belt objects with radar.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=216+Kleopatra&orb=1>, <en.wikipedia.org/wiki/216_Kleopatra>.
Ref:
-  S.J. Ostro, R.S. Hudson, M.C. Nolan, et al., 5 May 2000, Science, 288, 836, "Radar observations of asteroid 216 Kleopatra."
See: <adsabs.harvard.edu/abs/2000Sci...288..836O>;
-  P. Descamps, F. Marchis, J. Berthier, et al., 2011, Icarus, 211, 1022, "Triplicity and physical characteristics of asteroid (216) Kleopatra." See: <adsabs.harvard.edu/abs/2011Icar..211.1022D>.
-  T. Chanut, O.C. Winter, October 2012, American Astronomical Society, DPS meeting #44, #210.15, "Evaluation of the gravity field and the dynamic environment of asteroid 216 Kleopatra." See: <adsabs.harvard.edu/abs/2012DPS....4421015C>.
See also: <impact.arc.nasa.gov/news_detail.cfm?ID=38>, <newscenter.berkeley.edu/2011/02/22/how-kleopatra-got-its-moons/>, <www.planetary.org/blog/article/00002926/>, <www.space.com/11836-asteroid-kleopatra-moons-rubble-pile.html>.

E. Asphaug, Nature, 402, 127, "Survival of the weakest." See: <www.nature.com/nature/journal/v402/n6758/full/402127a0.html>, <adsabs.harvard.edu/abs/1999Natur.402..127A>.

Leonid Fireball over Dagali (Norway). See: <apod.nasa.gov/apod/ap991202.html>.

A.W. Harris, J.K. Davies, 1999, Icarus, 142, 464, "Physical characteristics of Near-Earth Asteroids from thermal infrared spectrophotometry." See: <adsabs.harvard.edu/abs/1999Icar..142..464H>.

877 NEAs known, of which 215 PHAs. See: <neo.jpl.nasa.gov/stats/>.

2000

The 100,000^th minor planet was numbered at the Minor Planet Center: inner main-belt asteroid 100000 Astronautica (1982 SH1, H = 16.9 mag, D ≈ 1.5 km), discovered on 28 September 1982 by J. Gibson at Palomar Observatory (CA, USA). This minor planet has been named Astronautica to recognize the 50^th anniversary of the beginning of the Space Age, inaugurated by the launch of the first artificial earth satellite on 4 October 1957, Sputnik. The name Astronautica is associated with this significant number, as space is defined to begin at an altitude of 100,000 meters above the Earth's surface.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1982+SH1&orb=1>, <en.wikipedia.org/wiki/100000_Astronautica>.

Bisei Spaceguard Center established in Bisei (Okayama, Japan). See: <en.wikipedia.org/wiki/Bisei_Spaceguard_Center>, <www.spaceguard.or.jp/ja/index.html>.

A. Deutsch, V.L. Masaitis, F. Langenhorst, R.A.F. Grieve, 2000, Episodes 23(1), 3, "Popigai, Siberia - well preserved giant impact structure, national treasury, and world's geological heritage." See: <en.wikipedia.org/wiki/Popigai_crater>.

R.A.F. Grieve, 2000, Annual Review of Earth and Planetary Sciences, 28, 305, "Vredefort, Sudbury, Chicxulub: three of a kind?" See: <adsabs.harvard.edu/abs/2000AREPS..28..305G>.

D. I. Steel, 2000, Target Earth (Time Life 2000; Readers Digests 2001). With an afterword by Arthur C. Clarke. See: <en.wikipedia.org/wiki/Duncan_Steel>.

L. Jetsu, J. Pelt, 2000, Astronomy & Astrophysics, 353, 409, "Spurious periods in the terrestrial impact crater record." See: <adsabs.harvard.edu/abs/2000A%26A...353..409J>.

L. Foschini, P. Farinella, C. Froeschlé, et al., 2000, Astronomy & Astrophysics, 353, 797, "Long-term dynamics of bright bolides." See: <www.geosociety.org/pubs/gsatoday/archive/sci0008.htm>, <adsabs.harvard.edu/abs/2000A%26A...353..797F>.

D.A. Kring, 2000, GSA Today, 10(8), 1, "Impact events and their effects on the origin, evolution and distribution of life." See: <www.geosociety.org/pubs/gsatoday/archive/sci0008.htm>, <www.lpi.usra.edu/science/kring/cataclysm_concept.pdf>.

2000, Jan 1

The University of Pisa puts its NEO Close Approach Monitoring system (CLOMON) on-line. See: <newton.dm.unipi.it/neodys/>.

D. C. Jewitt, 2000, Nature, 403, 145, "Eyes wide shut." See: <adsabs.harvard.edu/abs/2000Natur.403..145J>, <www.nature.com/nature/journal/v403/n6766/full/403145a0.html>, <impact.arc.nasa.gov/news_detail.cfm?ID=44>, <www.bibliotecapleyades.net/ciencia/ciencia_nemesis09.htm>.

D. Rabinowitz, E. Helin, K. Lawrence, S. Pravdo, 2000, Nature,  403, 165, "A reduced estimate of the number of kilometre-sized near-Earth asteroids". See: <adsabs.harvard.edu/abs/2000Natur.403..165R>.

2000, Jan 18

The Tagish Lake Meteorite exploded in the upper atmosphere at an estimated altitude of ~ 40 km with an energy of 1.7 kT TNT over Tagish Lake (Yukon Territory and northern British Columbia, Canada). A fireball was observed and over 500 fragments of meteorite collected. The Tagish Lake meteoroid is estimated to have been of D ≈ 4.5 m in diameter and M ≈ 75 tons in weight before it entered the Earth's atmosphere. It is estimated that only 1.3 tons remained after ablation in the upper atmosphere and several fragmentation events, meaning that around 97% of the meteorite had vaporized. Of these 1.3 tons of fragmented rock, only 0.1% was found and collected. Studies of the reflectance spectrum of the meteorite indicate that it likely originated from 773 Irmintraud, a D-type main-belt asteroid.
Ref:
-  T. Hiroi, M.E. Zolensky, C.E. Pieters, 2001, Science, 293, 2234, "The Tagish Lake Meteorite: a possible sample from a D-type asteroid." See: <adsabs.harvard.edu/abs/2001Sci...293.2234H>;
- A.R. Hildebrand, P.J.A. McCausland, P.G. Brown, et al., 2006, Meteoritics &Planetary Science, 41, 407, "The fall and recovery of the Tagish Lake Meteorite." See: <adsabs.harvard.edu/abs/2006M%26PS...41..407H>.
- C.D.K. Herd, A. Blinova, D. Simkus, 201, Science, 332, 1304, "Origin and evolution of prebiotic organic matter as inferred from the Tagish Lake Meteorite." See: <www.sciencemag.org/content/332/6035/1304.abstract?sid=22a6dae6-2ea2-4c33-a0a6-5937339f249b>.
See also: <impact.arc.nasa.gov/news_detail.cfm?ID=37>, <www.scientificamerican.com/article.cfm?id=ancient-meteorites-from-o>.

NASA/ESA spacecraft Cassini/Huygens took pictures of main-belt asteroid 2685 Masursky.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=2685+Masursky&orb=1>.
See also: <ciclops.org/view/76/Masursky_Flyby?js=1>, <uanews.org/node/2841>, <www.nasa.gov/pdf/474203main_Coradini_ExploreNOW.pdf>.

2000, Feb

The Japanese Spaceguard Association (JSGA) starts operations at Bisei Spaceguard Center (0.5 m and 1.0 m telescopes), Bisei, Japan.
Ref:
-  M. Yoshikawa, A. Asami, D. Asher, et al., 2002, Memorie della Società' Astronomica Italiana, 73, 772, "Current status of asteroid observations in Bisei Spaceguard Center." See: <adsabs.harvard.edu/abs/2002MmSAI..73..772Y>.

P. Michel, V. Zappalà, A. Cellino, P. Tanga, 2000, Icarus, 143, 42, "Estimated abundance of Atens and asteroids evolving on orbits between Earth and Sun." This paper defines the Inner-Earth Objects (IEOs). See: <adsabs.harvard.edu/abs/2000Icar..143..421M>.

C.R. Chapman, 2000, in: D. Sarewitz, R.A. Pielke, R. Byerly (eds.), Prediction: Science, Decision Making, and the Future of Nature (Washington DC: Island Press), p. 107, "The asteroid/comet impact hazard: homo sapiens as dinosaur?" See: <www.boulder.swri.edu/clark/ncar799.html>, <impact.arc.nasa.gov/news_detail.cfm?ID=57>.

2000, Mar

Between August 1972 and March 2000, the US Air Force Early Warning Satellites sensors detected 518 impact events (~30 events per year) in the > 1kT TNT class, i.e. impacts of objects with D ≈ few meters. Most of these events were primarily bursts in the upper atmosphere and were not detected at ground level. See: <impact.arc.nasa.gov/news_detail.cfm?ID=43>.

D.W. Dunham, B. Cudnik, D.M. Palmer, et al., 2000, in: 31st Annual Lunar and Planetary Science Conference, March 13-17, 2000, Houston (Texas, USA), abstract no. 1547, "The first confirmed video recordings of lunar meteor impacts." See: <adsabs.harvard.edu/abs/2000LPI....31.1547D>.

D.P. Rubincam, W.F. Bottke, 2000, in: 31^st Annual Lunar and Planetary Science Conference, 13-17 March 2000, Houston (TX, USA), Abstract no. 1399, "The YORP effect and the spin of small asteroids." YORP stands for Yarkovsky-O’Keefe-Radzievskii-Paddack.
Ref:
- V.V. Radzievskii, 1952, Astron. Zh., 29, 162, "A mechanism for the disintegration of asteroids and meteorites." See: <adsabs.harvard.edu/abs/1952AZh....29..162R>;
- S.J. Paddack, 1969, Journal Geophysical Research, 74, 4379, "Rotational burning of small celestial bodies: effects of radiation pressure." See: <adsabs.harvard.edu/abs/1969JGR....74.4379P>;
-  J.A. O’Keefe, 1976, Tektites and their origin, (Amsterdam: Elsevier). See: <adsabs.harvard.edu/abs/1976tto..book.....O>;
- V.V. Sazonov, 1994, Solar System Research, 28, 152, "Motion of an asteroid about its center of mass due to torque from light pressure." See: <adsabs.harvard.edu/abs/1994SoSyR..28..152S>.
See also: <www.lpi.usra.edu/meetings/lpsc2000/pdf/1399.pdf>.

2000, Apr

R.P. Binzel, 2000, Planetary and Space Science, 48, 297, "The Torino Impact Hazard Scale." See: <adsabs.harvard.edu/abs/2000P%26SS...48..297B>.

D.K. Yeomans, 2000, Nature, 404, 829, "Small bodies of the Solar System." See: <adsabs.harvard.edu/abs/2000Natur.404..829Y>.

E. Asphaug, 2003, Scientific American, 282, 46, "The small planets." See: <>.

A. Milani, S.R. Chesley, A. Boattini, G.B. Valsecchi, 2000, Icarus, 145, 12, "Virtual impactors: search and destroy." See: <adsabs.harvard.edu/abs/2000Icar..145...12M>.

S.N. Ward, E. Asphaug, 2000, Icarus, 145, 64, "Asteroid impact tsunami: a probabilistic hazard assessment." See: <adsabs.harvard.edu/abs/2000Icar..145...64W>.

Morávka (Czech Republic) Meteorite Fall. Occurred on May 6, 2000, 11:52 UT, during the daytime. Six H56 ordinary chondrites with a total mass of 1.4 kg were recovered. The corresponding fireball was witnessed by thousands of people and video-taped by three casual witnesses. Sonic booms were recorded by 16 seismic stations in the Czech Republic and Poland and by one infrasonic station in Germany.
Ref:
-  J. Borovička, P. Spurný, P. Kalenda, E. Tagliaferri, 2003, Meteoritics & Planetary Science, 38, 975, "The Morávka meteorite fall. 1. Description of the events and determination of the fireball trajectory and orbit from video records." See: <adsabs.harvard.edu/abs/2003M%26PS...38..975B>.

2000, May 16

"Near-Earth Object meeting has quite an impact." Representatives of ESA and other European organizations gathered in Paris to discuss the threat from Near-Earth Objects (NEOs). Non-ESA participants included the General Secretary of the International Astronomical Union (IAU), delegates from several ESA member states, experts from a number of astronomical observatories including the European Southern Observatory (ESO), and a representative from the European Community. The purpose of the meeting was to define a European strategy for the protection of the planet from Near-Earth Objects – asteroids and comets which pass close to the Earth's orbit. See: <astronomy2009.esa.int/science-e/www/object/index.cfm?fobjectid=19110>.

W.F. Bottke, D.P. Rubincam, J.A. Burns, 2000, Icarus, 145, 301, "Dynamical evolution of main belt meteoroids: numerical simulations incorporating planetary perturbations and Yarkovsky thermal forces." See: <adsabs.harvard.edu/abs/2000Icar..145..301B>.

W.F. Bottke, R. Jedicke, A. Morbidelli, et al., 2000, Science, 288, 2190, "Understanding the distribution of  Near-Earth Asteroids." Paper predicts ~900 NEAs with D > 1 km. At the  time ~40% had been found. See: <adsabs.harvard.edu/abs/2000Sci...288.2190B >.

M.V. Sykes, R.M. Cutri, J.W. Fowler, et al., 2000, Icarus, 146, 161, "The 2MASS asteroid and comet survey." See: <adsabs.harvard.edu/abs/2000Icar..146..161S>.

B. Gladman, P. Michel, C. Froeschlé, 2000, Icarus, 146, 176, "The Near-Earth Object population." See: <adsabs.harvard.edu/abs/2000Icar..146..176G>.

2000, Jul 9-12

International conference on Catastrophic Events & Mass Extinctions: Impacts and Beyond, Vienna (Austria). Proceedings: C. Koeberl & K.G. MacLeod (eds.), 2002, Geological Society of America Special Papers, Vol. 356, "Catastrophic events and mass extinctions: impacts and beyond." See: <adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001ceme.conf.3142O&db_key=AST>.
See also: <impact.arc.nasa.gov/news_detail.cfm?ID=46>.
Paper:
- J.T. Wasson, M.B.E. Boslough, 2001, "Large Aerial Bursts; an important class of terrestrial accretionary events." See: <adsabs.harvard.edu/abs/2001caev.conf.3152W>.

V. Garshnek, D. Morrison, F.M. Burkle, 2000, Space Policy, 16, 213, "The mitigation, management, and survivability of asteroid/comet impact with Earth." See: <www.sciencedirect.com/science/article/pii/S0265964600000254>.

A. Milani, S.R. Chesley, G.B. Valsecchi, 2000, Planetary and Space Science, 48, 945, "Asteroid close encounters with Earth: risk assessment." See: <adsabs.harvard.edu/abs/2000P%26SS...48..945M>.

D. Morrison, 2000, Physics Today, 53, no. 8, p. 14, "Moon yields info on near-Earth asteroids." See: <adsabs.harvard.edu/abs/2000PhT....53h..14M>.

B. Schwarzschild, 2000, Physics Today, 53, no. 8, p. 21, "Survey halves estimated population of big Near-Earth Asteroids." See: <adsabs.harvard.edu/abs/2000PhT....53c..21S>.

E.F. Tedesco, K. Muinonen, S.D. Price, 2000, Planetary and Space Science, 48, 801, "Space-based infrared near-Earth asteroid survey simulation." See: <adsabs.harvard.edu/abs/2000P%26SS...48..801T>.

J. Tichá, M. Tichý, Z. Moravec, 2000, Planetary and Space Science, 48, 787, "Klet' Observatory NEO follow-up programme." See: <adsabs.harvard.edu/abs/2000P%26SS...48..787T>.

J. Tichá, M. Tichý, Z. Moravec, 2000, Planetary and Space Science, 48, 955, "The importance of follow-up observations for newly discovered NEOs." See: <adsabs.harvard.edu/abs/2000P%26SS...48..955T>.

2000, Aug 1

The Spaceguard Survey, which has the objective of finding 90% of the NEAs with D > 1 km (defined as brighter than absolute magnitude H = 18) by 2009, is now approximately half complete (by number of objects, not by time required). Through the end of June 2000, 410 of these larger NEAs have been discovered. See: <impact.arc.nasa.gov/news_detail.cfm?ID=34>.

2000, Aug 14

IAU XXIV General Assembly, Manchester (UK). Division III Working Group on Near-Earth Objects (WG-NEO) meeting. Report by David Morrison, chair of the WG.
Ref:
-  H. Rickman (ed.), 2001, IAU WG-NEO Report, Transactions IAU XXIVB, (San Francisco: ASP), p. 139, "Working Group on Near-Earth Objects." See: <adsabs.harvard.edu/abs/2001IAUTB..24.....R>.

2000, Aug 16

H. Atkinson, C. Tickell & D. Williams (eds.), 2000, Report of the UK Task Force on Potentially Hazardous Near Earth Objects presented to the DG of the British National Space Center (BNSC), published 18 September 2000. As a result, BNSC created a NEO Information Center in Leicester (UK).
See: <impact.arc.nasa.gov/gov_UK_neotask.cfm>.
Ref:
-  I.P. Williams, 2007, in: A. Milani, G.B. Valsecchi & D. Vokrouhlický (eds.), Proc. IAU Symp. No. 236 on Near Earth Objects, our Celestial Neighbors: Opportunity and Risk, Prague (Czech Republic), 14-18 August 2006 (Cambridge: CUP), p. 471, "The UK Near Earth Objects Information Centre (NEOIC)." See: <adsabs.harvard.edu/abs/2007IAUS..236..471W>.
See also: <www.nearthearthobject.co.uk>, <www.greatdreams.com/near.htm>, <impact.arc.nasa.gov/news_detail.cfm?ID=33>, <impact.arc.nasa.gov/news_detail.cfm?ID=29>,
<impact.arc.nasa.gov/news_detail.cfm?ID=28>,
<impact.arc.nasa.gov/news_detail.cfm?ID=104>.

D.W. Hughes, 2000, Monthly Notices of the Royal Astronomical Society, 317, 429, "A new approach to the calculation of the cratering rate of the Earth over the last 125 ± 20 Myr." See: <adsabs.harvard.edu/abs/2000MNRAS.317..429H>.

2000, Sep 11-15

3^rd  International Conference on Space Protection of the Earth (SPE-2000), Evpatoria (Ukraine). See: <impact.arc.nasa.gov/news_detail.cfm?ID=47>, <impact.arc.nasa.gov/news_detail.cfm?ID=3>.

R.P. Binzel, 2000, Science, 289, 2065, "Asteroids come of age." See: <www.sciencemag.org/content/289/5487/2065.summary?sid=07315ef2-c90b-4465-839a-dc2946cc0fbc>.

D. Vokrouhlický, A. Milani, 2000, Astronomy & Astrophysics, 362, 746, "Direct solar radiation pressure on the orbits of small near-Earth asteroids: observable effects?" See: <adsabs.harvard.edu/abs/2000A%26A...362..746V>.

D. Vokrouhlický, P. Farinella, 2000, Nature, 407, 606, "Efficient delivery of meteorites to the Earth from a wide range of asteroid parent bodies." See: <adsabs.harvard.edu/abs/2000Natur.407..606V>.

Asteroid 4179 Toutatis (1989 AC,  H = 15.3 mag, D = 4.6×2.4×1.9 km, orbital P = 4.03 yr, PHA) passed Earth at 28.7 LD. It is the largest  known PHA.
See: <ssd.jpl.nasa.gov/sbdb.cgi?sstr=1989+AC&orb=1>, <en.wikipedia.org/wiki/4179_Toutatis>.
Ref:
-  R.S. Hudson, S.J. Ostro, D.J. Scheeres, 2003, Icarus, 161, 346, "High-resolution  model of asteroid 4179 Toutatis." See: <adsabs.harvard.edu/abs/2003Icar..161..346H>.
See  also: <science.nasa.gov/science-news/science-at-nasa/2000/ast31oct_1/>, <newton.dm.unipi.it/neodys/index.php?pc=1.1.8&n=Toutatis>.

R.S. Hudson, S.J. Ostro, R.F. Jurgens, et al., 2000, Icarus, 148, 37, "Radar observations and physical model of asteroid 6489 Golevka." See: <adsabs.harvard.edu/abs/2000Icar..148...37H>.
6489 Golevka, 1991 JX, H = 19.2 mag, D ≈ 530 m, NEA, PHA.

P. Pravec, A.W. Harris, 2000, Icarus,  148, 12, "Fast and slow rotating asteroids." See: <adsabs.harvard.edu/abs/2000Icar..148...12P>.

D.P. Rubincam, 2000, Icarus, 148, 2, "Radiative spin-up and spin-down of small asteroids." See: <adsabs.harvard.edu/abs/2000Icar..148....2R>.

J. Tate, 2000, Space Policy, 16(4), 261, "Avoiding collisions: the Spaceguard Foundation." See: <www.sciencedirect.com/science/article/pii/S0265964600000369>.

D. Vokrouhlický, A. Milani, S.R. Chesley, 2000, Icarus, 148, 118, "Yarkovsky effect on small Near-Earth Asteroids: mathematical formulation and examples." See: <adsabs.harvard.edu/abs/2000Icar..148..118V>.

Karel A. van der Hucht, IAU EC Advisor, <k.a.van.der.hucht@sron.nl>
SRON Netherlands Institute for Space Research, Utrecht, the Netherlands

Raquel Yumi Shida (ESO)

19 March 2013