When a rock suddenly appeared in front of the Opportunity rover on Mars last month, scientists were puzzled. Now, scientists at NASA’s Jet Propulsion Lab say they’ve solved the mystery.
https://gizmodo.com/this-mysterious-rock-just-appeared-in-front-of-our-rove-1503489334
Back in January when the rock — which scientists helpfully described as “about the size of a jelly doughnut” — was first spotted, a number of different options for how it got there were thrown around including that the rover itself had done it, a meteorite strike, and aliens (except not, because it wasn’t).
https://gizmodo.com/nasa-sued-for-failing-to-analyze-alien-life-1511430221
So, who was the culprit? Opportunity itself it turns out. The rover rolled over a larger rock, first breaking it, and then kicking a fragment — Pinnacle Island, as the rock eventually became known — over with its wheel to land right in front of the camera at just the right moment.
Scientists figured it out by following a time-honored detective’s trick — they followed the tracks. “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,” Opportunity chief Investigator Ray Arvidson explained in a statement. “We drove over it. We can see the track. That’s where Pinnacle Island came from.”
Image: NASA/ JPL
