The phrase "dark side of the Moon" usually refers to the side of the Moon that we cannot see from Earth. The Moon takes about 29 days to orbit the Earth. It takes almost the same amount of time to make one rotation on its axis. That is why we always see the same side of the Moon from Earth. This part of the Moon is not really the "dark side", however, it is more accurately the "far side". The side of the Moon we do not see from Earth gets just as much sunlight on it as the side we do see. In truth, the only dark side of the Moon is the side that is pointed away from the Sun at any given time.
The StarChild site is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC.
The StarChild Team
StarChild Graphics & Music: Acknowledgments
StarChild Project Leader: Dr. Laura A. Whitlock
Responsible NASA Official: Phil Newman