Last night, at 02:56 UTC, it was the 42nd anniversary of humans putting a bootprint on another world. Before Apollo 11 touched down on the Moon, though, NASA and the USSR sent a fleet of unmanned probes there. Since that time we’ve sent many more, including the Lunar Reconnaissance Orbiter, one of my favorite spacecraft of all time. It takes amazing high-res images of the Moon… and to celebrate today’s anniversary, they released this mysterious picture:

Cooool. Click to enlunenate.

This image is about 400 meters across, and shows an impact site with two lobes of material laid down to the sides. This butterfly-shape is a clear indication of a low-angle impact; it’s seen on many bodies in the solar system including the Moon, Mars, and even Earth (though the physics of exactly how the bi-lobed patterns form is still not well understood). Features like this are very rare… but it’s known that when a satellite orbit decays, it will impact at a low angle.

As the LRO site notes, in October 1967, the Lunar Orbiter 2 spacecraft impacted the lunar surface, possibly very near this spot. ...