A Global Data Base of 433Eros Lineaments

The Near-Earth Asteroid Rendezvous NEAR-Shoemaker spacecraft orbited the asteroid 433Eros for a year from 2000-2001. The NEAR Multi-Spectral Imager (MSI) collected tens of thousands of high resolution images and as a result Eros is the most comprehensively studied asteroid in the solar system. Previous mapping of lineaments on Eros has supported the suggestion of planes throughout the asteroid. We are creating a global data base of all Eros lineaments to better understand the global distribution of these features. It is particularly challenging to map lineament orientations on a non-spherical body (Eros is the shape of a peanut, measuring 34 km on the long axis). To address this issue we are mapping the lineaments directly on the Eros shapefile using POINTS, developed by J. Joseph at Cornell University. We compare lineament orientation to impact craters to determine if there is a causal relationship between cratering events and lineament formation. For example, preliminary mapping around Narcissus crater indicate at least four groups of lineaments: 1) previously mapped lineaments that may be indicative of planes through Eros, 2) lineaments radial to Narcissus crater, 3) lineaments related to nearby Shoemaker Regio, and 4) a set of lineaments that appear to be conjugate to set 1. Lineament sets 1 and 4 are also evident near Selene crater, as are lineaments radial to the crater. Lineament types include grooves, ridges and pit chains. We identify types of lineaments across the surface using a combination of NEAR Laser Rangefinder (NLR) topographic data and MSI images, and classify them according to region, including areas suggestive of thicker regolith. Further lineament/crater interactions are also examined, to determine the effect that lineaments have on crater shape.