Charon is Pluto’s largest moon, but it is relatively tiny for the Solar System at just 754 miles in diameter (compared to Pluto’s 1,473-mile diameter). One of five moons orbiting the dwarf planet (the others are Nyx, Hydra, Kerberos, and Styx), Charon was long thought to be a relatively boring, crater-pocketed world, at least as far as its terrain goes. But thanks to the New Horizons flyby, we now have access to the closest views of Charon ever captured—and they don’t disappoint. The images reveal this little alien moon is actually a fascinatingly diverse world, with a humungous canyon system stretching over 1,000 miles East to West across its meridian (about four times the length of the Grand Canyon, as NASA points out its news release). As John Spencer, a member of the New Horizons Geology, Geophysics and Imaging team put it in a statement provided by NASA: “It looks like the entire crust of Charon has been split open.” That may actually be fairly close to what happened on Charon in the past, because the canyon was clearly the result of some massive geologic or tectonic shift. NASA stitched some of the new images together into a breathtaking video flyby of Charon, as well. The new images have also led scientists to conclude that the smoother, less crater-dotted region of plains located just below the canyons in Charon’s southern hemisphere —a spot they’re calling “Vulcan Planum”— is a more recently-formed landscape. The fewer number of craters indicates the landscape hasn’t had as much time to be battered by meteors as other parts of Charon, and that there was some more relatively recent geological activity in the area, in order to smooth over any previously existing craters. Even more exciting is the possibility that Charon could have once had a subsurface ocean of liquid water, which later froze, then cracked open releasing lava to the surface, helping to form the new smooth terrain. And if you think these views of Pluto’s biggest moon are great, you’re in luck: more and closer images captured by New Horizons are being processed and should be released in the coming months. That should help scientists learn even more about this mysterious world at the edge of our Solar System.
