While we sent up a rover to check out the surface of Mars, it turns out we’re more likely to find life on the one of the MOONS of some of our other planets–for instance, on the moon of Saturn. What about the moons of Mars?
Saturn’s moon Enceladus is just a lump of rock 310 miles in diameter, but it’s constantly sending out plumes of ice particles, water vapor and trace organic compounds from its surface, and many astronomers think that exploring it should be our next space mission.
In the Observer, Robin McKie quotes astrobiologist Charles Cockell as saying, "If someone gave me several billion dollars to build whatever space probe I wanted, I would have no hesitation. I would construct one that could fly to Saturn and collect samples from Enceladus. I would go there rather than Mars or the icy moons of Jupiter, such as Europa, despite encouraging signs that they could support life. Primitive, bacteria-like life forms may indeed exist on these worlds but they are probably buried deep below their surfaces and will be difficult to access. On Enceladus, if there are lifeforms, they will be easy to pick up. They will be pouring into space."
McKie quotes NASA astrobiologist Chris McKay as saying, "It just about ticks every box you have when it comes to looking for life on another world. It has got liquid water, organic material and a source of heat. It is hard to think of anything more enticing short of receiving a radio signal from aliens on Enceladus telling us to come and get them."