Dr. Joshua Emery

December 20, 2006

“Greeks Bearing Gifts: Determination of the Surface Compositions of Trojan Asteroids from NIR Spectroscopy and Spectral Modeling”

NNG05GG80G

The goal of this task is to investigate the surface compositions of Trojan asteroids, to be accomplished by spectral mixing modeling of a rich set of as-yet unpublished near-infrared (NIR) reflective data as well as through collecting and modeling new spectral data over the wavelength range 0.8–4.0 µm using ground-based observatories. The new observations will focus mainly on smaller Trojans than have previously bee studied. Smaller objects are statistically more likely to have undergone recent collisions, and therefore are expected to have “fresh’ surfaces that reveal bulk (primordial) composition. We expect to observe 50 new Trojans, tripling the current dataset. Modeling these and the unpublished data will increase the number of Trojan asteroids that are quantitatively modeled by a factor of 5 or more.