Spitzer Space Telescope - Guaranteed Time Observer Proposal #88


Extinct Comets and Low-Albedo Asteroids

Principal Investigator: Dale Cruikshank
           Institution: NASA-Ames

Science Category: asteroids 
 Observing Modes: IrsMap IrsStare 
  Hours Approved: 15.4 

Abstract:
Several objects classified as asteroids have orbits that are
dynamically similar to those of comets.  They are thought to be comets
that have devolatilized by repeated passages through the inner solar
system.  Some of these objects are "near-Earth asteroids".  This is a
spectroscopic study of a sample of these objects.  For spectroscopic
comparison of the extinct comets, and for a parallel study of the
compositions of low-albedo main belt and Trojan asteroids, a number of
C, P, and D-type asteroids are included.