I recall when the book originally came out a lot of people said the scenario was implausible, so I have questions: * If you’ve only simulated 1000 pieces, what

I recall when the book originally came out a lot of people said the scenario was implausible, so I have questions: * If you’ve only simulated 1000 pieces, what is the likelihood they just don’t hit each other? (Space is pretty big.) * How big does a chunk have to be to not burn up on hitting the atmosphere? (This energy would obviously go somewhere, just not necessarily into impact.) * How and when does the moon reform?