It's hard to say where life (or past life) is most likely to be found, I think. It's only after the most recent rover (Curiosity) arrived at Mars that we disco

It's hard to say where life (or past life) is most likely to be found, I think. It's only after the most recent rover (Curiosity) arrived at Mars that we discovered clear evidence of long-lived lakes and streams on ancient Mars, and chemical species compatible with life (http://science.sciencemag.org/content/343/6169/1242777.full http://science.sciencemag.org/content/343/6169/1242777.full).