Tardigrades are awesome, but what about those unaging jellyfish?
I mean yeah still not quite the same thing. IE obviously I don't see jellyfish surviving in space. But do tardigrades age?
Which side note it looks like they do... while they can basically go in suspended animation, waterbears seem to have about a 3 year lifespan.
So, these guys are virtually unkillable for 3 years, but Turritopsis dohrnii while it can be killed, can live forever.