What's cool is this is practically a pristine contact binary, two objects that are orbiting each other so closely, they are actually touching each other.
Very similar to the Rosetta comet that was visited earlier, Comet 67P, but this one has been "weathered" by impacts and out gassing as it nears the sun:
Ultima Thule (pronounced TooLee) is in near perfect condition. Initial analysis is showing very few impact craters.