10-50 year event?
If indeed it was a 0.5 MT impact event by a 65ft diameter asteroid, an event you say should happen every 10-50 years on the moon...Then there should
be similar events happening on Mars
every 2.5-12.5 years on Mars [cause of its size].
The MGS images of Mars over the past five years should be thoroughly scrutinized for "before & after" images, revealing possible new impacts by asteroids...At 1.4 meter/pixel resolution, even I realize that a fresh crater on Mars over 50 meters in diameter should be quite evident to the MGS imaging system.
Jacob