PI: Peter Tamblyn, Binary Astronomy & Southwest Research Inst., email@example.com
Address: Department of Space Studies, 1050 Walnut St.\ \#400, Boulder, CO 80302, USA
CoI: William J. Merline, Southwest Research Institute
CoI: Clark Chapman, Southwest Research Institute
CoI: \mboxDavid Nesvorny, Southwest Research Institute
Title: Visible Light Curves of Exceptionally Young Asteroids
Abstract: In this second semester, we propose to obtain visible lightcurves for approximately 20 additional young asteroids. Changes from last semester's proposal are greater emphasis on ground-based support of our Spitzer program, and a corresponding shift to the 2.1 m telescope for one run. These observations leverage the recent discovery by Co-I \NESV that 96 known asteroids are products of the extremely recent breakup of a 25 km asteroid. These objects hold profound promise for our understanding of asteroid evolution because of their extraordinary youth, 5.8+/-0.2 My. Their observational characteristics reflect their initial surface and dynamical properties, which is not true of older asteroids. The observations we propose here have dual purposes. First, to measure the initial lightcurve amplitude and period distributions of fragments from an asteroid collision. As part of our NASA and NSF research, these will be compared with hydrocode simulations of family-producing collisions. Second, these observations will support Spitzer measurements of the thermal flux from an additional ~ 8 of these young asteroids. By combining the thermal observations with these proposed visual measurements of reflected sunlight, sizes and albedos can be determined. The sample was selected to test for size or age correlations with albedo. Finally, these and related observations will measure sizes, densities, albedos, rotation rates, and obliquities in this population. These properties relate directly to Co-I \NESV's novel measurement of the Yarkovsky Effect, an important driver of the long- term dynamical evolution of asteroids.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360