NASA has finally determined where it Jelly Donut came from. While there was confusion surrounding its seemingly random appearance, and some speculation about alien fungus, unfortunately, the true story falls a bit short of the exciting hypotheses.
When NASA found the rock sitting in front of Opportunity, there was shock and uncertainty, and there was no shortage ideas of how the rock appeared. There had been thoughts that it had been knocked by Opportunity, and simply landed in that position, but there was at least one that thought it was an alien fungus, spurring a lawsuit against the agency. But it turns out NASA was correct from the start. In a statement released from Ray Arvidson, he clarifies that “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.” From the pictures that Opportunity was able to capture after backing up slightly, it is clear that there are track marks next to a larger rock of the same composition as the mystery rock.