This is just bonkers, and is going to be, I think, the major scientific accomplishment of the MU69 flyby. Geophysicists did not predict this. Back to the drawing board! Isn't that fun?

You can read more about the discovery and observations at the New Horizons website, but I want to take the rest of this post to enjoy other weird-shaped space crescents.

New Horizons has taken a couple of other good ones. Here's a crescent Nix. Not many pixels, but a funky looking crescent!