Photos: How the (missing) Apollo tapes were made

Data storage in the late 1960s was a far cry from the multigigabyte disks of today. Machines like the ones pictured here recorded a scant 15 minutes of data on each 14-inch reel; as one reel neared completion, another would begin recording automatically with a slight overlap from the preceding tape to ensure data continuity.

Power limitations on the Apollo 11 spacecraft meant that the video had to be sent from the moon in a special slow-scan format that recorded just 10 frames per second. For broadcast over commercial television, the original signal had to be converted to 60 frames per second. The conversion to the U.S. broadcast signal took place simultaneously with the original data being recorded onto the magnetic tapes--and with a concurrent loss of image quality for TV viewers.

Photo by NASA