LeilaBattison

Still living - probably at the bottom of the ocean inside Europa - it's warm enough there for chemistry and biology to do its stuff, and it's shielded from radiation by an icy crust. The only challenge is to get there - it'll involve flying to Europa, drilling/melting through the ice, and then piloting a submersible from millions of miles away - like this awesome picture

It is the coolest job ever!

Really astrobiology explores blue-sky research which is always a bit hard to defend, except for the natural human curiosity to know whether we are alone, and how we got here...

But an awesome comeback is to mention all of the stuff that we use day to day that were developed as part of an apparently 'pointless' space exploration program. Without NASA we wouldn't have TV satellite dishes, medical imaging like MRI scans, barcodes, firefighter equipment, smoke detectors, anything aerodynamic, space pens, joystick controllers, and most plastics!

I love enceladus! But I was already concious I was making my answer too long, so would only talk about the obvious ones.

You're right, some scientists think they've found amino acids in the geysers, so its a first step towards earth-like life. We're still missing other good bits of evidence though, and even the ocean underneath isn't certain - it could just be fleeting bursts of hot ice...

1) I think it is possible - comets are thought to have delivered the earth's water, and organic compounds like amino acids have been found associated with comets. This is just one of the ideas for the origin of life by panspermia.

But panspermia as a theory is riddled with problems. If life was delivered by comets, was it as fully formed cells, or as DNA, or just organic molecules (which form on earth just fine). And if they're on the comet, how did they get to be there? Panspermia just shifts the big problem of the origin of life away from our own planet (which we can understand to some extent), to an unspecified place and time in the vast extent of the universe. Not a very good theory then.

Yeah maybe - and that's where astrobiologists have to start being a bit creative!

At the moment, we only really have to tools to recognise earth-like life, things with cells and DNA and a solvent to lubricate it all. But even our (many) definitions of life are hazy, and sometimes overlap with the replicating of computers, or the adaptability of viruses. The problem is being able to recognise them!