NASA Scientists Perplexed by Mysterious Mars Rock Unlike Anything They've Ever Seen Before

Life on Mars has yet to be found, although the Curiosity rover did find some compelling evidence last year that the Red Planet once had free-flowing, liquid water on its surface. That is about as exciting as things have gotten during NASA's explorations of Mars, until recently when a mysterious rock appeared on the planet's surface that wasn't there just a few weeks ago.

NASA scientists are perplexed, and have never seen anything quite like this before. Furthermore, it is unlike anything else they've seen on Mars itself to date.

Lead Mars Exploration rover scientist Steve Squyres describes the rock as looking like a large jelly donut, explaining:

“It looks white around the edge in the middle and there’s a low spot in the center that’s dark red – it looks like a jelly doughnut.”

The instruments on NASA's Opportunity rover that are analyzing the rock are sending back to Earth data that is as mysterious as the jelly donut-like rock itself. Squyres says:

“It’s like nothing we’ve ever seen before. It’s very high in sulphur, it’s very high in magnesium, its got twice as much manganese as we’ve ever seen in anything on Mars."

Due to bad weather, Opportunity has been stuck photographing the same region of Mars for more than a month, which is how the rock's appearance was even discovered. Scientists at the Jet Propulsion Laboratory in California have been monitoring the images that the rover has been sending back to Earth.

Two images of the area in question were taken. One shows the land with the rock, and an older image shows the land without the rock. Squyres says these images were taken no more than two weeks apart. Opportunity had not yet driven over the spot where the rock was pictured in the second photo, so how the rock got there is a mystery that NASA scientists are now actively trying to solve.

Researchers currently have two theories that could explain how the rock got where it did. One possibility is that the rover churned it up and threw it with its wheels. Because the rover didn't drive over that spot yet, it would have had to have thrown the rock quite a distance. This theory seems like the most likely scenario. The other possibility is that the rock was caused by a meteor, which would mean that nearby there's a smoking hole where the meteor impacted. The scientists do not see any such smoking hole nearby.

Speaking at an event marking the 10th anniversary of the arrival of NASA rovers Opportunity and Spirit on the Martian surface, Squyres added:

"I don’t know what any of this means. We’re completely confused, and everyone in the team is arguing and fighting (over what it means). That’s the beauty of this mission… what I’ve realized is that we will never be finished. There will always be something tantalizing, something wonderful just beyond our reach that we didn’t quite get to – and that’s the nature of exploration.”