A peculiar photograph taken by NASA’s Perseverance rover had people amused, then intrigued. The image shows a white and gold (or is it black and blue?) cylinder behind the rover. People on Reddit wondered if the rover accidentally dropped something. Others online joked that it might have been aliens or space junk.

But the reality is often stranger than fiction.

First of all, that is indeed a piece from the rover – an abrasion bit for its drill to be precise. It was placed on the Perseverance rover before launch and was always designed to be dropped after a test, as it might have been exposed to atmospheric contamination on Earth.

It was used in a rock and then abandoned there back in July. There is an informative Twitter thread on the rover page explaining why it did just that.  

As you can see in the image, the drill is stuck in the rock back in July. However, in the image from a few weeks ago, it is clearly on its side. So what happened? It was certainly not the wind, given how tenuous the atmosphere of Mars is.

Fans of the rover, and in particular Mars Guy on Youtube, have a better explanation: Perseverance ran over it. And it did it by itself, without human intervention.

The rover is currently retracing its steps to move to another location in Jezero Crater, the famous delta where a river once flowed into a lake. A lot of this drive was done by the autonomous self-driving software which broke several daily distance records. The software can avoid rock and boulders, and it is certainly possible that it hit the drill bit as it passed through the same spot again.

So not only did the rover “litter” Mars, like an unruly teenager, it even gave it a kick as it passed by it again.