NASA Lays to Rest Mars' Rock Mystery

Remember when the weird "jelly doughnut" object on Mars made news last month? NASA scientists were happily baffled after it suddenly appeared in images taken by the Opportunity rover. They're baffled no more: Scientists today said they're sure that the object is indeed a rock that got kicked into the camera's view by the rover itself, reports Fox News. (That had been a leading theory at the time, though imaginative skeptics weren't convinced.)

They figured it out with some old-fashioned sleuthing, notes i09—"they followed the tracks" from the rock (now named Pinnacle Island). "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," says a NASA statement. "We drove over it. We can see the track. That's where Pinnacle Island came from." (Click to see what Earth looks like from Mars.)