I'm a couple of days behind on this one, but it's too cool not to post about.
Stuff hits the Moon all the time -- in fact, I just blogged about this recently. All that junk orbiting the Sun sometimes hits us, and we see a meteor. The Moon is smaller, and has less gravity, so it gets hit less often, but it does get the occasional smacking.
Some NASA scientists got one on video recently. That is very cool. Years ago, I was thinking of getting some funding to monitor the Moon with a small telescope and a video camera; the idea would be to take every frame of video and subtract the frame before it. Any change would pop up as a bright spot in the image. I thought about it quite a bit, and decided it would take too much effort on my part, and I dropped it.
But others had the same idea, and implemented it. That's where the video above came from (click it for a link to a bigger version). Now, without outside verification it's not possible to know if this is an impact for sure or not, but it seems likely. The flash represents the sort of impact you'd expect randomly, and the way it brightens and dims also is consistent with an impact. What we need are 'scopes separated around the Earth viewing this, so we do get independent confirmation.
By studying these impacts we can get a better handle on how much stuff is out there and how often it hits the Moon. In 50 years, folks will be making their homes on the Moon, and this might have an immediate effect on their living conditions!'