Searching for life on Mars

Could Mars be teeming with life, but we just haven't been looking for it in the right way? Could our past efforts actually have destroyed organisms inadvertently? One scientist thinks so.

In the '70s, the Viking mission found no signs of life. But it was looking for Earth-like life, in which salt water is the internal liquid of living cells. Given the cold dry conditions of Mars, that life could have evolved on Mars with the key internal fluid consisting of a mix of water and hydrogen peroxide, said Dirk Schulze-Makuch, author of the new research.

That's because a water-hydrogen peroxide mix stays liquid at very low temperatures (-68 degrees Fahrenheit), doesn't destroy cells when it freezes, and can suck scarce water vapor out of the air.

The Viking experiments of the '70s wouldn't have noticed alien hydrogen peroxide-based life and, in fact, would have killed it by drowning and overheating the microbes, said Schulze-Makuch, a geology professor at Washington State University.

This is all very intriguing, but I think we should be exploring Mars with a focus on eventual colonization. Seeking and finding Martian microbes is a laudable endeavor, but even more important is finding another home for our species.