NSF Award
9113204
Dr. Clark Chapman at the Planetary Science Institute will implement an observing program to obtain spectrophotometric colors on a set of approximately 100 main-belt asteroids in the 2-20 km diameter size range. These data will enable him to identify taxonomic types of these asteroids and will thus provide a statistically significant sample of the distribution of types that exist among small main-belt asteroids. Dr. Chapman will compare the distribution of types for small asteroids with those of larger asteroids and will use the results to address several fundamental science questions about asteroids. Among these are: (i) Are there parent bodies for the ordinary chondrite meteorites among the small main-belt asteroids? (ii) are there significant numbers of small olivine-rich asteroids? (iii) Does the size distribution of small S-type asteroids flatten at sizes less than 20 km diameter? Dr. Chapman will acquire Charge Coupled Device observations in eight filters in the wavelength range of 0.35 micron to 1.1 micron using 1m and 2m telescopes. An important part of this program is to establish faint standard stars in the eight-color system located at regular intervals along the ecliptic plane. Dr. Chapman will also obtain rotation periods and lightcurve amplitudes of a subset of the asteroids observed.
