Physics
Scientific paper
May 2000
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000icar..145..108b&link_type=abstract
Icarus, Volume 145, Issue Icarus, pp. 108-121.
Physics
37
Scientific paper
Asteroids or comets striking a planetary surface at very shallow angles produce elliptical-shaped craters. According to laboratory impact experiments (D. E. Gault and J. A. Wedekind 1978, Proc. Lunar Planet. Sci. Conf. 9th, 3843-3875), elliptical craters result from impact angles within ~5° of horizontal and less than 1% of projectiles with isotropic impact trajectories create elliptical craters. This result disagrees with survey results which suggest that approximately 5% of all kilometer-sized craters formed on Mars, Venus, and the Moon have elliptical shapes. To explain this discrepancy, we examined the threshold incidence angle necessary to produce elliptical craters in laboratory impact experiments. Recent experiments show that aluminum targets produce elongated craters at much steeper impact angles than sand targets. This suggests that target properties are as important as the projectile's impact angle in determining the eventual ellipticity of the crater. Creating a model which interpolates between impact data produced using sand and aluminum targets, we derive a new elliptical crater threshold angle of 12° from horizontal for Mars, Venus, and the Moon. This leads to a predicted proportion of elliptical craters that matches observations within uncertainty given a random projectile population. We conclude that the observed proportion of elliptical craters on these bodies is a natural by-product of projectiles striking at random angles, and that no additional formation mechanisms are needed.
Bottke William F.
Glotch Timothy
Love Stanley G.
Tytell David
No associations
LandOfFree
Interpreting the Elliptical Crater Populations on Mars, Venus, and the Moon does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Interpreting the Elliptical Crater Populations on Mars, Venus, and the Moon, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interpreting the Elliptical Crater Populations on Mars, Venus, and the Moon will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1194905