To celebrate the 1000th day of its Lunar Reconnaissance Orbiter, NASA has created an animation showing the 4.5-billion-year history of the moon.

It follows the moon from its formation -- when a planet hit Earth and reabsorbed the resulting debris -- to the volcanic activity that formed the moon's maria and then the formation of craters.

One of the LRO's main projects is an ultra-high-resolution moon map, so it's only fitting to celebrate the orbiter with a look at how the lunar landscape originally formed.

[badastronomer]