Yeah. Punch it. In my regular form, I can punch the ground hard enough to cause earthquakes. But when I have all seven Chaos Emeralds, I can go into a Super form that gives me way, way more strength. I don't HAVE any Chaos Emeralds.... but I mean, if we can find 'em and somehow get me up there, then maybe I can fix this. I never tried punching anything that big that hard, but it couldn't make things any worse, I figure.

Or even if I can't smash the moon, maybe I can dig enough tunnels through it that it gets weak enough to blow apart with a bomb? Dunno how big the moon ACTUALLY is or whatever, but I can dig real fast.