Letters of Intent for 2015

LoI 2015-211
Asteroids: New Observations, New Models

Date: 3 August 2015 to 14 August 2015
Location: Honolulu, Hawaii, United States
Contact: Steven Chesley (steve.chesley@jpl.nasa.gov)
Coordinating division: Division F Planetary Systems and Bioastronomy
Co-Chairs of SOC: Steven Chesley (JPL/Caltech)
Alessandro Morbidelli (Observatoire de la Côte d'Azur)
Robert Jedicke (IfA/Univ. Hawaii)
Chair of LOC: ()



- Asteroid families
- YORP & Yarkovsky effects
- Multiple systems, asteroid pairs
- Asteroid mass, density, porosity, internal structure
- NEA transport
- NEA physical properties - as a test of main-belt models
- Trojans and Centaurs - connections to the main belt
- Main-belt comets/activated asteroids
- Main belt orbital/physical structure - as a test of solar system formation theories
- Dust/meteor formation and transport
- Cratering record on dwarf planets



Asteroids are the small, usually rocky, bodies that reside primarily in a belt between Mars and Jupiter, although they have been scattered throughout the solar system to varying degrees. The current dynamical structure of the asteroid belt and the physical properties of its constituents serve as a constraint on the evolution of the early solar system. Near-Earth asteroids have been transported from the main belt deep into the inner solar system where they can be studied in greater detail by ground-based telescopes and can be reached by exploratory space missions. Because of their origin in the main belt, understanding the near-Earth asteroid population provides critical constraints on the current main belt, which in turn feed into our understanding of the early solar system.

The main asteroid belt is a lively place where the physical, rotational and orbital properties of asteroids are governed by a complicated interplay of collisional evolution, planetary resonances, radiation forces, and the formation and fission of secondary bodies. Of particular importance is the subtle effect of thermal emissions that can alter the spin state of a body (YORP effect) or slowly drive the orbit into resonances (Yarkovsky effect), which can cause the body to rapidly evolve out of the main belt. All of these mechanisms are integrally coupled, increasing the complexity of the system. For example, the YORP-induced rotational evolution depends critically on an asteroid's shape, even as collisions alter the shape and spin state of asteroids. Similarly, the Yarkovsky effect depends on the spin state, which is continually changing due to collisions and the YORP effect. The formation of companion bodies can follow abruptly from catastrophic collisions or more gradually from the YORP effect, and the evolution of these multi-body systems is again subject to the complicated dynamical environment that defines the asteroid belt.

This symposium will focus on synthesizing our understanding of the dynamical and physical properties of asteroids, which will serve to improve our understanding of our solar system and provide clues to understand its past and future evolution. Related populations that inform this understanding, such as Jupiter Trojans, near-Earth asteroids, dust and meteoroids will be within the scope of the meeting.