Earthset from the Lunar Reconnaissance Orbiter
			
		
		
		
			On the Moon, the Earth never rises -- or sets. 
If you were to sit on the surface of the Moon, you would see the Earth just hang in the sky.
This is because the Moon always keeps the 
same side toward the Earth.
Curiously, the featured image does picture the Earth setting over a lunar edge. 
This was possible because the image was taken from a spacecraft  orbiting  the Moon - specifically the 
Lunar Reconnaissance Orbiter (LRO).
In fact, LRO orbits the Moon so fast that, from the spacecraft, the 
Earth appears to 
set anew about every two hours.
The featured image 
captured one such Earthset about three months ago. 
By contrast, from the surface of the Earth, the 
Moon sets about once a day -- with the 
primary cause being the rotation of the Earth.
LRO was launched in 2009 and, 
while creating a detailed three dimensional map of the 
Moon's surface, 
is also 
surveying the Moon for 
water and possible good landing spots for 
future astronauts.