If the heat source would be heavily radioactive, is it likely that some lifeform not caring about it would have evolved there? Or a lifeform with rather limited lifespan?

Well, at the moment I'm not hoping for life (I am, but you know what I mean ). But if the idea of water at earth temperatures is correct, that's amazing news. I hope they can find good evidence for that.

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To the regular visitor of internet bulletin boards it is clear that it's an excellent idea your parents get to choose your real name.