No, a “checklist error” did not almost derail the first moon landing

Enlarge / Apollo 11’s Eagle moves slowly away from Columbia and prepares for landing. (credit: NASA / Apollo Lunar Surface Journal)

Update: It’s Fourth of July weekend in the US, and Ars staff is off presumably safely operating fireworks and catching some R&R. With the 50th anniversary of the Apollo 11 moon landing rapidly approaching, this felt like the perfect time to resurface a few favorite NASA stories from the archives. If our recent six-part documentary or report from a restored Mission Control haven’t quite satiated your moon landing needs, this piece on the infamous Apollo 11 landing alarms might do the trick. It originally ran on July 28, 2015 and appears unchanged below.

Last week was the forty-sixth anniversary of the Apollo 11 moon landing—the first of the six crewed landings on our nearest celestial neighbor. In the years between 1969 and 1972, 12 human beings walked on the surface of the moon: Neil Armstrong, Buzz Aldrin, Pete Conrad, Al Bean, Alan Shepard, Ed Mitchell, Dave Scott, Jim Irwin, John Young, Charlie Duke, Jack Schmitt, and Gene Cernan. Each Apollo landing by necessity leapfrogged the previous by some notable amount, because even as Apollo 11 was preparing to lift off it was obvious that the money wasn’t coming and Project Apollo might be the only chance to visit the moon—perhaps for a long, long time.

Even though Apollo 10’s “dress rehearsal” had taken NASA through all but the final phase of the lunar landing two months before, there were still a large number of unknowns in play when Neil Armstrong and Buzz Aldrin separated Eagle from Columbia, leaving Michael Collins to watch his crewmates descend to the lunar surface—perhaps to stay there forever.