Men and women have been rocketing into space from the Earth’s surface for the past half-century — long enough that much of the general public now views space missions as relatively safe, rote endeavors. Sure, inconceivably complex and technically nuanced projects like setting an SUV-sized state-of-the art roving laboratory on the surface of Mars — without breaking it — can still grab the world’s attention. For countless people, however, when it comes to manned missions like the discontinued Space Shuttle program or flights to and from the International Space Station, the thrill is long gone.
But the business of space exploration is not, and has never been, safe. Explosions, fires, parachute failures and other disasters have left scores of astronauts, cosmonauts, test pilots and crew workers dead and wounded through the years. Some (Challenger and Columbia, for example) are spectacular, terrifying catastrophes. Others are smaller, quieter calamities — but for anyone involved who survives, injured or not, the experiences are life-changing.
Here, LIFE.com recalls one of the worst disasters in NASA’s history — and its first public tragedy — when astronauts Gus Grissom, Ed White and Roger Chaffee died in a fire inside their command module on a Cape Canaveral launchpad on Jan. 27, 1967. As TIME’s Jeffrey Kluger (the author of Apollo 13) once wrote, when commemorating the three astronauts:
The program, of course, survived, and less than three years after the 1967 launchpad fire, Neil Armstrong, Buzz Aldrin and Michael Collins flew Apollo 11 to the moon and back — leaving human footprints on the lunar surface — in what some consider the signature triumph of the 20th century.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter at @LizabethRonk.