The mystery of the now infamous "jelly doughnut" rock on Mars has been solved, according to NASA, which reports that the rock was moved by the wheel of its Opportunity rover.
The rock, dubbed Pinnacle Island by the space agency, grabbed headlines earlier this year after it seemed to appear out of nowhere. Photos taken by the Opportunity about two weeks apart showed the same patch of Martian land, the former lacked the distinctive rock present in the latter. The rock came to be known as the jelly doughnut because of its white-rimmed, red centered appearance, and because it's about the size of a doughnut.
Spectators around the world used Internet comment forums to voice their opinion on the origins of the rock, or whether it was a rock at all. One man's theory - that the rock was a "mushroom-like fungus" - led him to sue NASA for failing to investigate what he believed to be a living thing on the surface of Mars.
The space agency, however, reports it is confident that the jelly doughnut is part of a larger rock that was struck by the Opportunity rover's wheel. After moving the rover away from the site of the mysterious rock, new images reveal a larger piece of rock slightly uphill from the site of the Pinnacle Island rock.
"Once we moved Opportunity a short distance, after inspecting Pinnacle Island, we could see directly uphill an overturned rock that has the same unusual appearance," said Opportunity Deputy Principal Investigator Ray Arvidson of Washington University in St. Louis. "We drove over it. We can see the track. That's where Pinnacle Island came from."
NASA said a chemical analysis of the rocks revealed they are made of the same materials, which solidifies its position that the rocks are one in the same.