- Jan. 27, 1967: Astronauts Gus Grissom, Edward H. White and Roger B. Chaffee die when a fire sweeps their command module during a ground test at Kennedy Space Center.
- April 24, 1967: Soviet cosmonaut Vladimir Komarov is killed when his Soyuz I spacecraft crashes on return to Earth.
- June 29, 1971: Cosmonauts Georgy Dobrovolsky, Vladislav Volkov and Viktor Patsayev die during re-entry of their Soyuz 11 spacecraft. A government commission disclosed that the three died 30 minutes before landing because a faulty valve depressurized the spacecraft.
- Jan. 28, 1986: The space shuttle Challenger explodes 73 seconds after launch, killing all seven astronauts aboard, including Christa McAuliffe, intended to be the first teacher in space. Other astronauts killed were Francis ``Dick'' Scobee, Michael J. Smith, Ellison S. Onizuka, Judith A. Resnik, Ronald E. McNair and Gregory B. Jarvis.
- Feb. 1, 2003: Space shuttle Columbia breaks apart in flames about 203,000 feet over Texas, 16 minutes before it was supposed to touch down in Florida. All seven aboard were killed: William McCool, Rick Husband, Michael Anderson, Kalpana Chawla, David Brown, Laurel Clark and Ilan Ramon, who was Israel's first astronaut.