You've got a world roughly 400 million miles from Earth just a little
smaller than our Moon covered in a crust of ice miles thick over a
global ocean of briny, acidic liquid water up to SIXTY MILES deep.

The beauty part is, because Europa is smaller than Earth, the
pressure at the bottom is no worse than about 7 miles deep in
our planet's oceans. Heavy, but not intolerable as a 60-mile
deep Earth ocean would be. With the other moons and Jupiter
churning things up, it is quite possible that Europa's ocean floors
are covered with active hydrothermal vents.

Plus Europa is surrounded by even larger moons, one with
numerous active volcanoes, another that is bigger than
Mercury and may have its own ocean deep down, and they
are all circling a gas giant planet that could hold 1,200 and
are constantly bathed in its powerful radiation fields.

After all this, finding life on Europa would just be the icing
on the cake. Amazing icing, but Europa is a place that was
once thought only to exist in science fiction - in fact, I can't
recall any SF before the Voyager flybys in 1979 that ever
described Europa in such an amazing way.