Two NASA probes, and now NASA has released the last video the spacecraft sent back to Earth. The video is a beautiful fly-by of the lunar surface.
The GRAIL mission, comprised of two identical satellites, was meant to map the moon's gravitational field to gain insights into its internal structure. The spacecraft -- named Ebb and Flow in a student naming contest -- had been flying in formation at extremely low altitudes since January 2012.
As the mission was coming to its end, NASA decided to spend the last of Ebb and Flow's fuel to crash the satellites into the moon. The twin spacecraft slammed into the lunar surface at more than a mile per second.
As the description in the video explains:
This video of the moon was taken by the NASA GRAIL mission's MoonKAM (Moon Knowledge Acquired by Middle School Students) camera aboard the Ebb spacecraft on Dec. 14, 2012.
At the time the images were taken, the spacecraft were about 6 miles above the northern hemisphere of the moon's far side, in the vicinity of the Jackson impact crater.
This imagery was acquired as part of a final checkout of spacecraft equipment prior to its planned impact on a mountain near the moon's north pole on Dec. 17.