Hi Mizzerie – It depends a lot on whether there is enough energy in the explosion to push pieces out of the moon’s current orbit. The moon is actually a fair way away, so minor changes in orbit of the chunks wouldn’t be so bad at first. Over time, the pieces would either re-clump, or get spread out into a rough ring (again, depending on what happened in the explosion).
In a really big explosion pieces of the moon might go into weird orbits, or even slow down enough in their orbit to spiral into the earth. That would be as bad as getting hit by a big asteroid. Big pieces in different orbits would also disrupt the tides, causing a lot of problems for sea-edge life that depends on tides.
An explosion wouldn’t be very good mizzerie – see Drew’s answer. But apart from the explosion and risk of getting hit part we would (obviously) get showered in cheese and we’d have to have a big fondue to get rid of it all.
Ok so that was a little silly… actually all the tides would stop – as the tides are caused by the moon’s gravitational pull – so there wouldn’t be any high or low tides. All the animals and plants that live in the intertidal regions all over the world would die as they need the tides to live. And lots of ships would get stuck in harbours or out at sea as they need high tides to get back home.
But on the upside, they wouldn’t be any werewolves at a full moon, so that’s a bonus. 🙂