A discarded Falcon 9 rocket will collide with the moon at 5,400 miles per hour.

An Abandoned SpaceX Rocket Is About to Crash Into the Moon: As the moon starts getting crowded, questions of safety and responsibility are becoming hard to ignore

"Watching this one gives us a rare chance to open up ejecta-plume science and calibrate those models against a real event, which matters for every future thing we deliver to the…