Apparently it's thought that meteorites hitting the ground freeze water around them after a bit. They get heated up, but it's pretty short, so the bulk of it is

Apparently it's thought that meteorites hitting the ground freeze water around them after a bit. They get heated up, but it's pretty short, so the bulk of it is "space temperature" only the surface is heating. And a lot of the stuff that heats up is ablated. (depending on size) Unless the stuff is on the surface of the meteorite it's probably fine.