A rock unlike anything scientists have seen before just appeared on Mars. So what is it?
In a new status report for the Mars Opportunity rover, NASA announced "encountering a surprise" on the Martian surface when the rover spotted a strange rock in an area where the rover had seen nothing only days earlier. The rover's been spending a lot of time in the same area of the surface lately due to weather conditions, and now it looks like going back over the same spot of ground may have paid off with this discovery, even if scientists don't know exactly what it means yet.
"We saw this rock just sitting here. It looks white around the edge in the middle and there’s a low spot in the centre that's dark red - it looks like a jelly doughnut," Mars Exploration lead scientist Steve Squyres said last week during a Jet Propulsion Laboratory event celebrating 10 of the Mars rovers.
"And it appeared, just plain appeared at that spot - and we haven't ever driven over that spot."
The photo on the left was taken a few weeks ago. The photo on the right was taken 12 Martian days after the first photo at the same spot, where you can now clearly see the "jelly doughnut." So how did it get there? Well, Squyres and his colleagues are betting on two primary theories: Either a meteor hit the planet somewhere nearby and this rock is a piece of debris from the strike, or the rover somehow disloged the rock from the surface as it drove by and knocked it onto that spot.
"We had driven a meter or two away from here, and I think the idea that somehow we mysteriously flicked it with a wheel is the best explanation," Squyres said.
Even if the mystery of how the rock arrived where it did is solved, though, the mystery of exactly what it's doing on Mars is not, particularly after analysis of the "jelly" portion of the rock came back from Opportunity's instruments.
"It's like nothing we've ever seen before," Squyres said. "It's very high in sulphur, it's very high in magnesium, it's got twice as much manganese as we've ever seen in anything on Mars.
"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)."
The Jet Propulsion Laboratory scientists will no doubt keep analyzing the rock in an effort to determine where it came from and what relationship it has to the Martian surface. In the meantime, we'll keep hoping it's evidence of aliens, and Squyres will keep touting it as evidence that our Martian journey really has just begun.
"That's the beauty of this mission... what I've realised is that we will never be finished," he said. "There will always be something tantalising, something wonderful just beyond our reach that we didn't quite get to - and that's the nature of exploration."
(Via The Independent)