I've always thought since the moon doesn't doesn't rotate around as it circles earth, that the 'Darkside of the Moon" was always blacked out. This CBC reported says that is inaccurate and that the backside of the moon gets "as much sunlight as earth? Really. I've got to read more about that.
PBS.org reports "We don’t see the far side because “the moon is tidally locked to the Earth,” said John Keller, deputy project scientist for NASA’s Lunar Reconnaissance Orbiter project. “The moon does rotate, but it rotates at the same speed that it rotates around the Earth.” The moon completes one full rotation on its axis in the time it takes to orbit the Earth. That means the same side is always turned toward us."