"And by the sun’s," Ivy added with a nod and a little smile. Which was why she was in charge of Izzy and Dinah wasn’t. She was willing to correct a Ph.D. marine biologist in front of a roomful of people, but she could carry it off in a way that didn’t sting. "But the answer is, probably surprisingly little. The moon’s mass is still all there, close to where it was before. It’s just spread out a little. But the pieces still have the same collective center of gravity, still in the same orbit as the moon had before. Your tide tables will still pretty much work."