STS-51-L

STS-51-L
NASA · Public domain · source
Name	STS-51-L
Mission type	Satellite deployment
Operator	NASA
Mission duration	1 minute, 13 seconds (achieved)
Spacecraft	Space Shuttle Challenger
Launch date	January 28, 1986, 16:38:00 UTC
Launch site	Kennedy Space Center, LC-39B
Landing site	Kennedy Space Center (planned)
Crew caption	The crew of STS-51-L
Insignia caption	Mission patch

STS-51-L was the twenty-fifth flight of the Space Shuttle program and the tenth mission for the Orbiter ''Challenger''. It was launched from Kennedy Space Center in Florida on January 28, 1986. The mission ended in catastrophic failure 73 seconds after liftoff, resulting in the loss of the orbiter and its seven-person crew. The disaster led to a 32-month hiatus in the Space Shuttle program and a comprehensive reassessment of NASA's safety culture and engineering practices.

Mission overview

The primary objective of STS-51-L was to deploy the Tracking and Data Relay Satellite-B (TDRS-B), a critical communications satellite for NASA. A secondary payload was the Spartan-Halley spacecraft, designed to observe Halley's Comet during its 1986 apparition. The mission also carried the Shuttle-Pointed Tool for Astronomy (SPARTAN) and several educational experiments as part of the Teacher in Space Project. The flight was highly publicized due to the presence of Christa McAuliffe, who was selected to be the first private citizen and teacher in space. The planned duration was six days, with a landing scheduled back at the Shuttle Landing Facility at Kennedy Space Center.

Crew

The crew consisted of seven members, representing a diverse cross-section of American expertise. Mission Commander Francis R. Scobee was a veteran of STS-41-C. Pilot Michael J. Smith was on his first spaceflight. The mission specialists were Ellison S. Onizuka, a veteran of STS-51-C; Judith A. Resnik, a veteran of STS-41-D; and Ronald E. McNair, a veteran of STS-41-B. The two payload specialists were Gregory B. Jarvis, an engineer from Hughes Aircraft, and Christa McAuliffe, the Teacher in Space from Concord, New Hampshire.

Space Shuttle Challenger disaster

The launch proceeded normally until approximately 73 seconds after liftoff at 11:39 EST. A failure in the joint of the right Solid Rocket Booster (SRB), exacerbated by the unusually cold temperatures at Kennedy Space Center that morning, allowed hot gases to breach the External Tank. This led to the structural failure of the External Tank and the rapid aerodynamic breakup of the orbiter. The crew cabin, while severely damaged, remained largely intact until it impacted the Atlantic Ocean. The event was witnessed live on television by millions of viewers, including many schoolchildren watching for Christa McAuliffe.

Investigation

President Ronald Reagan immediately appointed the Rogers Commission, chaired by former Secretary of State William P. Rogers, to investigate the accident. The commission included notable figures such as astronaut Neil Armstrong and physicist Richard Feynman. The investigation conclusively identified the cause as the failure of O-ring seals in the Solid Rocket Booster joint, which lost elasticity in the cold weather. The commission heavily criticized NASA's decision-making process, revealing a culture where managerial pressure had overridden engineering concerns raised by contractors like Morton Thiokol. Richard Feynman famously demonstrated the O-ring flaw during a televised hearing using a simple glass of ice water.

Aftermath and legacy

The Space Shuttle fleet was grounded for 32 months while the Solid Rocket Boosters were completely redesigned by Morton Thiokol and other safety and management changes were implemented at NASA. The families of the crew established the Challenger Center for Space Science Education to continue the educational mission. The disaster fundamentally altered NASA's risk assessment protocols and marked a significant shift in public perception of human spaceflight. Memorials were established at Arlington National Cemetery and the Kennedy Space Center Visitor Complex. The tragedy is commemorated annually on its anniversary during NASA's Day of Remembrance.

Category:Space Shuttle missions Category:1986 in the United States Category:Space accidents and incidents