Could these weird spheres be proof life once existed on Mars?

Contributed by
Dec 17, 2012, 4:24 PM EST

Two years ago, NASA's Opportunity Rover snapped images of "blueberries" on Mars, and scientists have been analyzing what they mean ever since. Now it seems these weird little spheres could be proof that life once existed on the Red Planet.

The "blueberries" were first thought to be evidence that liquid water once moved across the Martian surface, but new research suggests there's something bigger going on. Research conducted by scientists at the University of Western Australia and the University of Nebraska suggests that the spheres weren't formed by water, but rather by microbial organisms.

In a study published in last month's issue of Geology, the researchers reported analysis of similar iron-oxide balls found here on Earth. After tracking down our planet's own "blueberries" in places like the Jurassic Navajo Sandstone in Utah, the researchers discovered that microorganisms played a big part in their formation. Direct analysis hasn't been done on the Martian blueberries yet, but if the same formation process holds true for them, it would be proof that life (very very small life) once existed on the Red Planet.

The theory hasn't been confirmed yet, and even if it is it probably means life was last on Mars millions of years ago. But even if that's the case, this discovery could put us closer to definitive proof that other planets in our Solar System once supported life.

(Via Huffington Post)