Apollo 11: Mission Out of Control

For the next three minutes, the cratered lunar landscape grew closer, until, at around 46,000 feet, Armstrong rotated the vehicle, pointing the landing radar toward the surface while the astronauts turned to face Earth. The moon’s gravity is irregular, and to account for this, the astronauts had to take new measurements. With the void outside his window, Aldrin punched in a request to compare the lander’s calculated position with the reading from the radar. He was answered by a klaxon ringing in his earpiece. Aldrin hurriedly keyed in the two-digit code 5-9-Enter, which translated, roughly, as “display alarm.” The console responded with error code “1202.” Despite his months of simulations, Aldrin didn’t know what this one meant; Armstrong, equally baffled, …