Is the weird surface of the Uranian moon Miranda really due to its having broken apart and reassembled?
Probably not, but this is not to say that the moon hasn’t been shattered to bits in its past, or that its geology isn’t fascinating. Theoretical models indicate that a moon in the location and with the size of tiny Miranda (only about 500 miles in diameter) should have been shattered by large impacts several times in the very early days of the Solar System. The moon we know as Miranda is the last incarnation of such moon-breaking events, and its probably shows no sign of these past calamities. Its surface does show three giant ovoidal “coronae” with geological characteristics that suggest they formed due to upwelling of the surface from below. This can be explained by diapirism during a past episode of tidal heating of the tiny moon.
