Jonathan Silverlight wrote:


This should really be in sci..space.tech or sci.astro, but doesn't
some of the evidence for a fairly thin ice layer on Europa come from
the fact that it's all broken up, as though the individual icebergs
move relative to each other? There's a _lot_ of tidal strain keeping
things moving.

I don't think NASA spotted any movement during Galileo's mission, as
that would have been big news, and clinched the case for the water
layer...and there are _some_ meteor craters on the moon, so the surface
isn't getting remade on anything like a yearly basis.
Pat