Humble Pi: When Math Goes Wrong in the Real World

by Matt Parker

This tragedy led to a numerical quirk of the Apollo missions. Even though the spacecraft never launched, the mission with Gus Grissom, Edward White II, and Roger Chaffee was retrospectively named Apollo 1 out of respect for them, rather than keeping its codename, AS-204. Officially, the first actual launch should have been named Apollo 1, but AS-204 was declared to be the first official Apollo flight, despite the fact that it “failed on ground test.” This had a weird follow-on effect because, now, two previous crewless launches (AS-201 and AS-202; AS-203 was a payloadless rocket test and so not an official launch) were also retrospectively part of the Apollo program, even though they were never given Apollo names. The first Saturn V rocket launch thus became known as Apollo 4, giving us the niche bit of trivia that Apollo 2 and Apollo 3 never existed.