Minor Planet Center (MPC)

The Minor Planet Center (MPC) operates at the Smithsonian Astrophysical Observatory , under the auspices of  Division F of the International Astronomical Union (IAU).

The MPC is responsible for the designation of minor bodies in the solar system: minor planets; comets; and natural satellites. The MPC is also responsible for the efficient collection, (computation), checking and dissemination of astrometric observations and orbits for minor planets, comets and outer natural satellites, via the Minor Planet Circulars (issued generally on a monthly basis), the Minor Planet Circulars Orbit Supplement (MPO) (issued three to twelve times per year), the Minor Planet Circulars Supplement (MPS) (issued three or four times a month) and the Minor Planet Electronic Circulars (issued as necessary, generally at least once per day).

Please view the links to the MPC websites at: MPC for Observers and MPC for the Public.

IAU Centre for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference (CPS)

The International Astronomical Union (IAU) is deeply concerned about the increasing number of launched and planned satellite constellations in mainly low Earth orbits. The IAU embraces the principle of a dark and radio-quiet sky, not only as essential to advancing our understanding of the Universe of which we are a part, but also for the cultural heritage of all humanity and for the protection of nocturnal wildlife.

The IAU Centre for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference (CPS) coordinates collaborative multidisciplinary international efforts with institutions and individuals and works across multiple geographic areas to help mitigate the negative impact of satellite constellations on ground-based optical and radio astronomy observations as well as on humanity’s enjoyment of the night sky.