48 years ago today, astronauts first stepped foot on the moon. Re-live the moment now: http://nbcnews.to/2ue5jT3 #MakingOfAnAstronaut | NBC News Science

With the Apollo 15 moonwalk coming to an end on this day (August 2) in 1971, Commander Dave Scott told Mission Control in Houston, "There's something I think you'll find rather interesting..." He turned to the TV camera and showed the live TV audience, a hammer (in his right hand) and a feather (in his left hand) and pointed out that centuries earlier Galileo had said that without air resistance all objects would fall at the same rate of speed. Scott dropped the hammer and the feather from the s