No doubt in my mind that life exists there, from what I can gather methane gas in the atmosphere will dissipate very quickly. With the quantities that have been measured in the last few months scientists have come to the conclusion that some life form must be producing it. Especially when they think that water has not existed on the surface for quite some time. Once we find life there and I have no doubt that we will, we will know that we are not alone in the universe. If life can exist on two planets then it is likely that the entire universe is teeming with it. The only question then; are we the only intelligent life form or should I say sentient?
