Thanks Marcia! There are a lot of claims that that bug got there through post landing contamination, but since it's been demonstrated convincingly that spores can survive space vacuum, especially if shielded from direct sunlight, I don't see why he shouldn't have been there all along!

I'm adding spacecraft power systems to my list of possible habitats by the way; Nickel hydrogen batteries, used on some sattelites, contain an aqueos solution (26-31% potassium hydroxide) highly alkaline but still mostly water, not impossible something could call it home.

Regenerative fuel cells take the water formed by the reaction of Hydrogen and oxygen in a combustion chamber, and crack it back into more hydrogen and oxygen to be reused, but before that happens the water is stored in a tank, so another possible home.

I know I'm waffling on about this but I wonder if it's ever been properly looked into by a space agency? Life in space is a big research topic, lots of experiments on the ISS are devoted to it, and the genesat space craft was launched specifically to look into it.