The easiest explanation for methane is geology. However, when you look at the amount they found (minute at best), then biology is a better preliminary guess. Which is all it is on both sides of this argument at this point, a guess. Almost forty years ago we landed on the moon and thought all the myths of the past had been erased. But that same year we learned the most important lesson on extraterrestrial life ever. Our best scientists said without oxygen and sunlight life was impossible. Then all of a sudden we find hundreds of tube worms, crabs, and fish at the bottom of the ocean next to hydro thermal vents. Then we find out they exist breathing metal (chemosynthesis). All of a sudden everything we thought we knew went out the door and we were all children again, exploring our own back yard. Everywhere in our tiny solar system we have found methane has been in huge amounts, like the moons of Saturn and such. However, when we find small amounts you have to at least except that its fifty fifty on whether or not it was created by biology or geology. We will probably never know which one, even when we do actually go to mars and find signs of life either in the past or even present. When you look at all the major celestial objects within our reach, even some asteroids and comets have had micro organisms on them, or even still have them today, dormant or alive. It just makes sense that life is everywhere. Even if we can’t understand how. There are allot more ways for life to exist than just sunlight and oxygen, or heat and sulfur. I’m not even going to go into the alien thing. The geology side of this particular argument has merit and just as I know biology is a viable answer, it may very well be that both biology and geology produce or produced methane of mars. Yes, its still possible that geology alone produced it, but very unlikely. Just as its unlikely that biology alone produced it. The funny part of this question posed to write on is that it is adversarial. Why must there be only one “right” answer to some of these questions? Can you just imagine a room full of scientists trying to convince our government to spend millions of dollars just to prove something one way or the other? Governments only spend millions of dollars when both sides of a question are possible and both answers meet the “whats in it for me/us” factor. If we find methane produced by biology then finding that biology may be beneficial to our understanding of all life or even to medical research in the form of a cure for something. If we find geology produced it then maybe it could help us understand what direction mars is going or even be a possible form of energy to help future space exploration. Either way, these questions we take sides on have no right or wrong answers, even if its true good versus true evil. Finding methane is a good thing, no matter how it got there. Trying to determine only one way it got there is evil.
