Shades of Grey

Two streaks of high and low reflectance blocky ejecta from the same crater. A large boulder rests in the low reflectance deposit. LROC NAC M168862555R, image width is 500 m [NASA/GSFC/Arizona State University].

This unusual ejecta is blocky, and exhibits high and low reflectance, and is from a very fresh crater located in the lunar highlands at 3.348°N, 259.724°E. Blocky craters can happen when an impact occurs in a more coherent target material, but what about the difference between the reflectance?
Context image for today's featured image. Image width is 140 km [NASA/GSFC/Arizona State University].

The reflectance difference has two possible causes. The two ejecta streaks could be from separate craters, or the ejecta could be the result of compositional differences in the target rock. Since both ejecta streams point back to the unnamed crater, the ejecta contrast is most likely the result of a compositional difference in the subsurface. Since the context map shows that the higher reflectance ejecta is much more prevalent, a small lower reflectance rock layer is probably the culprit.

Can you find any other low reflectance boulders or ejecta in the full NAC frame?

Related Posts: Rubble Pile on Fresh Crater Floor

Dark streaks in Diophantus crater

Two-toned Impact Crater in Balmer Basin: A Reflection of the Target?

Published by Drew Enns on 22 November 2011