All right. Which one of you little green men of Mars did this?
The boulder left a visible track in the Martian regolith big enough to be spotted by MRO. But just one Martian year later, the tracks are gone, erased from existence.
“This is most likely due to the fine bright dust that is transported in the atmosphere falling down and re-covering the dark markings,” wrote Ross A. Beyer on the HiRISE site.
And just what do you think those sneaky Martians are trying to hide?