The moon seemed closer than ever last week when the hatch of an Apollo lunar vehicle opened and three smiling astronauts clambered out. In a giant vacuum chamber at Houston's Manned Spacecraft Center, the bearded, bone-tired trio had just spent eight days simulating a trip to the moon and back. Reported Spacecraft Commander Joseph Kerwin: "A prime reason for the mission was to come back and say 'Yes sir, the darned thing works.' We sure are going to be able to report that."
For NASA officials, the mock space voyage had particular significance. To prevent a repeat of last year's...