[LdSentinal]

Now let's get that submarine probe to Europa and get a look at what is swimming in the ocean under all that ice.

That would be difficult. You have to drill through miles of ice to get that ocean.

[J_Baird]

Not everywhere there are some areas that are very thin. You can see them in some of the photographs. Basically we land a nuclear powered heater on the surface with the probe inside it basically melts its way down with the probe inside.

[Strategerist]

It's tricky, but doable with a self-contained unit and like I said they're playing around with various designs to test in Antarctica (there are lakes there miles under the ice to study.)

The critical issue is whether the probe can be COMPLETELY sterilized so earth organisms aren't introduced to the oceans of Europa. That is harder to do than it seems.