“Repeated impacts, stresses from thermal cycling, and other forms of weathering on the lunar surface would all tend to break down rocks into more-or-less ‘spherical’ shapes, given enough time.
“Think of how rocky beaches wear down stones to smooth, round shapes over time by repeated jostling in the waves.”
The NASA-affiliated lunar geologist added both the rocky shard and the “ridge” running near the rock’s edge indicate this rock is geologically young and emplaced recently.
He said: ”I would definitely guess an origin as impact ejecta from some nearby crater.
