History.com: How Landing the First Man on the Moon Cost Dozens of Lives

NASA was preparing feverishly for a moon landing in a race against the former Soviet Union to honor slain president John F. Kennedy's 1961 pledge for the country to land a spacecraft on the moon (and return safely) before the end of the decade. America would meet that challenge on July 20, 1969, but the effort would be built on sacrifice and tragedy. Some eight astronauts and astronaut candidates died in airplane crashes or vehicle tests, many other NASA ground crew and workers perished during accidents, while dozens of test pilots died in the decades leading up to Apollo.