According to an article on Space.Com, Spirit and Opportunity aren’t going to find critters on the surface. Since the surface is harsh because of radiation, a safer environment might be found in caves. The discovery of soluble rock and methane is leading some to imagine that extensive caves might exist on Mars, and maybe that is where the methane is coming from. Could methane emissions be a signature of life? “The fact that you find methane does not mean you have to have life,” said Tobias Owen (U of Hawaii), one of the discoverers of methane on Mars (and also a member of the Huygens team). “You have to be very careful.” John Rummel agrees. He’s a NASA planetary protection advisor tasked with avoiding undue contamination of Mars (and, conversely, of Earth from Martian organisms). Apparently smarting from the fallout of the over-hyped Martian Meteorite saga of 1996, he said, “It’s an art of managing uncertainty. The public deserves an honest agency.”
We deserve it, but we’re not getting it. All the rhetoric about water indicating life and methane indicating life is giving NASA a bad name, at least among logically-minded people. Water is to life what iron is to a city. Cities need iron, but the element does not imply the other. Life is characterized by functional information – specified complexity – not the basic elements of which it is composed. Neither does finding earth-life in extreme environments imply it originated there by evolution, and astrobiologists know this. The public deserves an honest agency.