NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Cratering on GaspraThe October 1991 Galileo flyby of Gaspra shows that its crater population is dominated by fresh craters several hundred meters in diameter and smaller. They appear to represent a production population because the spatial density is relatively low (few overlaps) and because fresh craters are very abundant; equilibrium could be attained at diameters near to or below the resolution limit of the best image. These craters are the first direct record of the population of main-belt asteroids some tens of meters in diameter. Craters primarily from the highest resolution, 'high phase' image, on which over 600 craters are visible in 90 sq. km were counted, measured, and classified; earlier counts were made on the lower resolution four-color images, which show an order of magnitude fewer craters because of the resolution limit. The population index (exponent of the differential power law approximately describing the crater sizes) has a very high negative value (-4.3 +/- 0.3, meaning that the log-log slope is 'steep'), appreciably steeper than the value of -3.5 thought to reflect collisional equilibrium according to theory.
Document ID
19940007675
Document Type
Conference Paper
Authors
Chapman, Clark R. (Lunar and Planetary Inst. Houston, TX, United States)
Neukum, Gerhard (Deutsche Forschungsanstalt fuer Luft- und Raumfahrt Oberpfaffenhofen, Germany)
Veverka, Joseph (Cornell Univ. Ithaca, NY., United States)
Belton, Michael (Kitt Peak National Observatory Tucson, AZ., United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1993
Publication Information
Publication: Twenty-fourth Lunar and Planetary Science Conference. Part 1: A-F
Subject Category
LUNAR AND PLANETARY EXPLORATION
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Related Records

IDRelationTitle19940007055Analytic PrimarySixth Annual Workshop on Space Operations Applications and Research (SOAR 1992), volume 219940007543Analytic PrimaryTwenty-fourth Lunar and Planetary Science Conference. Part 1: A-F