Coming up with different and novel ways to destroy planets is lots of fun.
Just don't brag about it at your next job interview.
Commentary by memnarch (who has not seen the movie)
Yeeeeeeaah, I don't think this moon is going to be fixable for the next movie or Episode IX anymore. Heck, comic explanation aside, it almost looks like the destroyed sun reformed itself out of the hulk. Movie aside, it's still an excellent image to picture ships and asteroids rapidly flying backwards away from the planet as it time travels backwards. That'd even make for a good explanation of how Team Bad-Guy gets to show up in the next Episode; caught in a temporal vortex, they were all flung far from the moon and across the galaxy! Back to last week at the very least or perhaps to two weeks from now.
Any bets on how anyone on Team Bad-Guy actually survives? Assuming they did anyway. I'll guess that there isn't an explanation said or shown, but that we'll get a scene or two of Hux, Phasma, and Kylo all talking aboard a ship like the Finalizer. If this was a different kind of movie, I'd even guess that Kylo would only be able to glare at the other two as he'd be stuck in a bacta tank.
Transcript
GM: Explosive convulsions rock the moon as you take off.
[SFX]: Kaboom!
[SFX]: Boom!
[SFX]: Boom!
GM: Allan and the remaining X-wings join you.
Allan: This should be some hot planetary geology!
GM: Jim, what would it be like if the moon evolved backwards in time to a primordial state?
[SFX]: Boom!
Allan: Hmm. The crust would crumble and be subsumed by a ball of white-hot magma. With bombarding asteroids being flung off.
GM: Okay, that’s what happens.
Allan: Cool!!
Snap Wexley: Oh, sure, but when I describe a world’s destruction people say it’s weird.