The phrase comes from NASA mission control audio during the launch of Space Shuttle Challenger on 28 January 1986, when the capsule communicator confirmed the shuttle could throttle its main engines back up after max q. Seconds later, the shuttle broke apart, and the calm call became one of the most widely replayed moments from the mission's final audio. It has since circulated in documentaries, news retrospectives and online edits, where it is used to mark the contrast between routine launch procedure and the tragedy that followed.