Astronomy Tuesday

Earthrise.

The Earth never actually rises and sets from the perspective of the moon because the moon doesn't rotate -- it's always the same face pointing toward us. So the Earth just sits there, always at the same point in the sky.

But this picture was taken by the Lunar Reconnaissance Orbiter, which is orbiting the moon, and from its perspective the Earth appears and disappears, rising and setting every two hours.

Image Credit: NASA/GSFC/Arizona State U./Lunar Reconnaissance Orbiter