TRUST IN HARDWARE
During the race to the moon in the 1960s, the Apollo program was faced with the unprecedented
problem of guiding two manned spacecraft to a rendezvous in lunar orbit.4 Because of the speed-oflight
delay in radio transmissions to and from the moon, guidance from ground-based computers
would have an unacceptable delay from anything close to real-time, endangering the mission and
the lives of the astronauts. A better answer was to have on-board computation with minimal lag time
to help the pilots determine how to rendezvous the two spacecraft.
At that time, computers filled rooms and weighed tons. In order to build computer systems that
were small and lightweight enough to fly with the Apollo Command and Lunar Modules, NASA
engineers wanted to turn to the newly developed integrated circuit chips. The problem: these early
chips were not particularly reliable even for ground uses, let alone for mission-critical spacecraft
flight hardware.