Celestia Forums

Suppose that a planet, Earth-sized, had a companion roughly Mars-sized. now suppose the companion was struck at an oblique angle by a large asteroid, generating a ring of debris (as supposedly happened, according to one [outdated?] thoery regarding the KT impact). How long would that ring last, and could there be a point where, as the ring erodes, material from it (or even the original impact) would form another ring around the primary planet?

Yes, I'm looking for an excuse to create a double planet, with double rings. I don't care if the rings last only 1,000 years....

...John...