A launch pad fire during Apollo program tests at Cape Canaveral, Florida, kills astronauts Virgil “Gus” Grissom, Edward H. White II, and Roger B. Chafee. An investigation indicated that a faulty electrical wire inside the Apollo 1 command module was the probable cause of the fire. The astronauts, the first Americans to die in a spacecraft, had been participating in a simulation of the Apollo 1 launch scheduled for the next month.

The Apollo program was initiated by the National Aeronautics and Space Administration (NASA) following President John F. Kennedy’s 1961 declaration of the goal of landing men on the moon and bringing them safely back to Earth by the end of the decade. The so-called “moon shot” was the largest scientific and technological undertaking in history. In December 1968, Apollo 8 was the first manned spacecraft to travel to the moon, and on July 20, 1969, astronauts Neil A. Armstrong and Edwin “Buzz” Aldrin Jr. walked on the lunar surface. In all, there were 17 Apollo missions and six lunar landings.

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