Life on Mars? We've Been Wrong Before

13.04.2012
Thirty-six years ago, the Viking 2 Lander picked up some dirt and did some donuts on the surface of Mars. According to the computational data recorded then (and the fact that no one came out and kicked the lander off of their lawn), the red planet was stamped with a big "nothing to see here" sign; no life was found. Re-evaluation of the data is changing all of that, according to a newly published paper at .

So where's the life? Well, that's a complicated answer.

Scientists came to the original verdict after running tests on the soil samples that the Viking 2 returned with. The tests looked for microbial metabolism in soil--that is, evidence that something once lived there and left figurative wrappers and whatnot lying around when it left. It seemed pretty conclusive at the time that the evidence pointed to a pristine Martian landscape, untouched by skateboarding hipster microbes or bacteria.

But wait! An international team of mathematicians and scientists took a fresh and quirky look at the data, and came out with a different opinion. "On the basis of what we've done so far, I'd say I'm 99 percent sure there's life there," Joseph Miller, a researcher with the University of Southern California Keck School of Medicine, .

What'd they do, then?

The teams looked for complexity. A purely physical process--that is, your normal geological events like earthquake, wind, and so on--are not that complex. However, biological processes tend towards very high complexity data sets. They found the data correlated pretty well with existing examples of biological data sets here on Earth. While not bulletproof, the science of it is pretty compelling, especially to someone who's seen about a billion times.