When I was a kid, a gully was something behind someone’s house that filled up with water when it rained, and even though it seemed too gross to just walk in and swim in it, it was perfectly fine to swing into it from a rope haphazardly tied to a tree branch. There’s no app for that. Recent satellite imagery has revealed gullies on the asteroid Vesta, and researchers are now trying to figure out where they came from. Leave it to science to take all the fun out of gullies.
Mysteries are fun, though, and that’s what these eroded paths are, at least initially. NASA’s Dawn probe spent more than a year mapping Vesta’s surface from an altitude of 210 km., and finished this round of duties in September. Vesta is the second largest body in the asteroid belt between Mars and Jupiter. Jennifer Scully presented evidence at the American Geophysical Union Fall Meeting that, of the roughly 60 craters (10 km and wider) that she examined, 11 examples showed a series of complex paths cut into the rock, “They are longer and narrower. They also interconnect, branching off one another,” Ms. Scully explains. The remains of old Plinko games from extraterrestrial Price Is Right episodes?