This is one of my favourite YouTube Saturday videos for a long while and it comes from NASA's Goddard Space Flight Centre. The Moon was likely formed when a planet, roughly the size of Mars, collided with the early Earth around 4.5 billion years ago (Here's a previous YouTube Saturday post showing how the moon was formed). The resultant debris coalesced, underwent rampant volcanism and was bombarded by craters to form its current, seemingly sleepy, current state. The video was made using data from NASA's Lunar Reconnaissance Orbiter (LRO), a nifty robotic spacecraft currently orbiting the moon just 50km above the surface. Its mission is to map the lunar surface paying particular attention to the polar regions and a search for water in the permanently shaded regions of our moon's surface. The LRO is also responsible for targeting potential landing zones for future missions to the Moon. The LRO took this cool picture of the Apollo 11 Lunar Module too! The video is available in numerous formats on the Goddard Multimedia website.