Today marks the 43rd anniversary of 1972's iconic "blue marble" photograph, snapped by the crew of the Apollo 17 spacecraft -- the final Apollo mission, actually. Either Eugene Cernan, Ronald Evans or Jack Schmit took the photo en route to the moon (NASA credits all three). at a a distance of about 45,000 kilometers (28,000 miles). It's a rare photo, one of the few to show such a highly-illuminated Earth disk, as a photographer must position the sun directly behind them to capture the shot.
Thanks to Joe for bringing this to my attention!