Challenger launches at the start of STS-51-L. 73 seconds later, the shuttle's external tank would combust, causing the breakup of the shuttle and the deaths of all 7 crew on board.
NamesSpace Transportation System-25
Mission typeSatellite deployment
Mission duration6 days, 0 hour 34 minutes (planned)
1 minute 13 seconds (achieved)
Distance travelled18 mi (29 km)
Orbits completedFailed to achieve orbit
(96 planned)
Spacecraft properties
SpacecraftSpace Shuttle Challenger
Launch mass2,685,210 lb (1,217,990 kg)
Landing mass199,704 lb (90,584 kg) (planned)
Payload mass48,363 lb (21,937 kg)
Crew size7
Start of mission
Launch dateJanuary 28, 1986, 11:38:00 am EST
RocketSpace Shuttle Challenger
Launch siteKennedy Space Center, LC-39B
ContractorRockwell International
End of mission
DestroyedJanuary 28, 1986, 11:39:13 am EST
Landing dateFebruary 3, 1986, 12:12:00 pm EST (planned)[1]
Landing siteKennedy Space Center,
SLF Runway 33 (planned)
Orbital parameters
Reference systemGeocentric orbit (planned)
RegimeLow Earth orbit
Perigee altitude177 mi (285 km)
Apogee altitude183 mi (295 km)
Period90.40 minutes
Comet Halley Active Monitoring Program (CHAMP)
Fluid Dynamics Experiment (FDE)
Phase Partitioning Experiment (PPE)
Shuttle Pointed Autonomous Research Tool for Astronomy (SPARTAN-203)
Shuttle Student Involvement Program (SSIP)
Teacher in Space Project (TISP)

STS-51-L mission patch

Back row: Ellison S. Onizuka, S. Christa McAuliffe, Gregory B. Jarvis, Judith A. Resnik
Front row: Michael J. Smith, Francis R. "Dick" Scobee, Ronald E. McNair
← STS-61-C (24)

STS-51-L was the disastrous 25th mission of NASA's Space Shuttle program and the final flight of Space Shuttle Challenger.

Planned as the first Teacher in Space Project flight in addition to observing Halley's Comet for six days and performing a routine satellite deployment, the mission never achieved orbit; a structural failure during its ascent phase 73 seconds after launch from Kennedy Space Center Launch Complex 39B on January 28, 1986, killed all seven crew members —Commander Francis R. "Dick" Scobee, Pilot Michael J. Smith, Mission Specialists Ellison S. Onizuka, Judith A. Resnik and Ronald E. McNair, and Payload Specialists Gregory B. Jarvis and S. Christa McAuliffe—and destroyed the orbiter.

Immediately after the disaster, President Ronald Reagan convened the Rogers Commission to determine the cause of the explosion. The failure of an O-ring seal on the starboard Solid Rocket Booster (SRB) was determined to have caused the shuttle to break up in flight. Space Shuttle flights were suspended while the O-rings and other hazards that could have destroyed the vehicle on following missions were addressed. Shuttle missions resumed in September 1988 with STS-26, launched 32 months after the accident.

Planned mission

The tenth mission for Challenger, STS-51-L, was scheduled to deploy the second in a series of Tracking and Data Relay Satellites (TDRS-B), carry out the first flight of the "Shuttle Pointed Autonomous Research Tool for Astronomy" (SPARTAN-203) / Halley's Comet Experiment Deployable in order to observe Halley's Comet, and carry out several lessons from space as part of the Teacher in Space Project and Shuttle Student Involvement Program (SSIP). The flight marked the first American orbital mission to involve in-flight fatalities. It was also the first American human spaceflight mission to launch and fail to reach space; the first such mission in the world had been the Soviet Soyuz 18a mission, in which the two crew members had survived. Gregory Jarvis was originally scheduled to fly on the previous shuttle flight (STS-61-C), but he was reassigned to this flight and replaced by Congressman Clarence W. "Bill" Nelson.[2]


Position Astronaut
Commander Francis R. "Dick" Scobee
Would have been second spaceflight
Pilot Michael J. Smith
Would have been first spaceflight
Mission Specialist 1 Ellison S. Onizuka
Would have been second spaceflight
Mission Specialist 2 Judith A. Resnik
Would have been second spaceflight
Mission Specialist 3 Ronald E. McNair
Would have been second spaceflight
Payload Specialist 1 Gregory B. Jarvis
Would have been first spaceflight
Hughes Space and Communications
Payload Specialist 2 S. Christa McAuliffe
Would have been first spaceflight
Teacher in Space Project

Backup crew

Position Astronaut
Payload Specialist 1 L. William Butterworth
Would have been first spaceflight
Hughes Space and Communications
Payload Specialist 2[3] Barbara R. Morgan
Would have been first spaceflight
Teacher in Space Project
Morgan would be selected as a NASA astronaut in 1998 and flew on STS-118 in 2007 as a mission specialist.

Crew seating arrangement

Seat[4] Launch Landing
Seats 1–4 are on the Flight Deck. Seats 5–7 are on the Middeck.
S1 Scobee Scobee
S2 Smith Smith
S3 Onizuka McNair
S4 Resnik Resnik
S5 McNair Onizuka
S6 Jarvis Jarvis
S7 McAuliffe McAuliffe

Although the crew died in the Challenger disaster, their seating assignment chart depicts what would have happened if the mission had been performed as planned.

Ascent failure and disaster

Main article: Space Shuttle Challenger disaster

Challenger after the explosion 73 seconds after launch

During the ascent phase, 73 seconds after liftoff, the vehicle experienced a catastrophic structural failure resulting in the loss of crew and vehicle. The Rogers Commission later determined the cause of the accident to have been the failure of the primary and secondary (backup) O-ring seals on Challenger's right Solid Rocket Booster (SRB). The failure of these seals allowed a flamethrower-like flare to impinge upon one of two aft SRB attach struts, which eventually failed, freeing the booster to pivot about its remaining attachment points. The forward part of the booster cylinder struck the external tank inter-tank area, leading to a structural failure of the Space Shuttle external tank (ET) – the core structural component of the entire stack. A rapid burning of liberated propellants ensued. With the structural "backbone" of the stack compromised and breaking up, the SRBs flew off on their own, as did the orbiter, which rapidly broke up due to overwhelming aerodynamic forces. The launch had been approved despite a predicted ambient temperature of 27 °F (−3 °C), well below the qualification limit of major components such as the SRBs, which had been certified for use only at temperatures above 39 °F (4 °C).[5] Evidence found in the remnants of the crew cabin showed that several of the emergency Personal Egress Air Packs (PEAPs) carried by the astronauts had been manually activated, suggesting that forces experienced inside the cabin during breakup of the orbiter were not inherently fatal, and that at least three crew members were alive and capable of conscious action for a period following vehicle breakup.[6] "Tracking reported that the vehicle had exploded and impacted the water in an area approximately located at 28.64° north, 80.28° west".[7]

Crew fate

Divers from the USS Preserver located what they believed to be the crew cabin on the ocean floor on March 7, 1986. A dive the following day confirmed that it was the cabin and that the remains of the crew were inside.[8] No official investigation into the Challenger disaster has determined the cause of death of the astronauts; it is almost certain that the explosion itself did not kill the entire crew as 3 of the 4 Personal Egress Air Packs (PEAPs) that were recovered had been manually activated. This would only be done during an emergency or loss of cabin pressure. PEAPs do not provide a pressurized air flow and would still have resulted in the astronauts losing consciousness within several seconds.[9] There were media reports alleging that NASA had a tape recording of the crew panicking and on-board conversation following the explosion during the 2 minute 45 second free fall before hitting the sea east of Florida. This was likely fabricated and no recording exists, as the crew may have been unconscious from loss of cabin pressure and the astronauts did not wear individual voice recorders.[10]

Mission objectives

Attempt Planned Result Turnaround Reason Decision point Weather go (%) Notes
1 22 Jan 1986, 3:43:00 pm Rescheduled Delays in STS-61-C[1]
2 23 Jan 1986, 3:43:00 pm Rescheduled 1 day, 0 hours, 0 minutes Delays in STS-61-C
3 24 Jan 1986, 3:43:00 pm Scrubbed 1 day, 0 hours, 0 minutes Weather at transatlantic abort site
4 25 Jan 1986, 9:37:00 am Scrubbed 0 days, 17 hours, 54 minutes Launch preparation delays
5 27 Jan 1986, 9:37:00 am Scrubbed 2 days, 0 hours, 0 minutes Equipment failures in orbiter closeout, cross winds at shuttle landing site.
6 28 Jan 1986, 9:37:00 am Delayed 1 day, 0 hours, 0 minutes Technical issues with fire detection system.
7 28 Jan 1986, 11:38:00 am Loss of vehicle and crew 0 days, 2 hours, 1 minute [1]

Mission insignia

Francis R. "Dick" Scobee asked Kennedy Space Center engineer Ernie Reyes to design the mission patch seen above to represent the mission STS-51-L. In it, Challenger is depicted launching from Florida and soaring into space to carry out a variety of goals. Among the prescribed duties of the five astronauts and two payload specialists (represented by the seven stars of the U.S. flag) was observation and photography of Halley's Comet, backdropped against the U.S. flag in the insignia. Surnames of the crew members encircle the scene, with the payload specialists being recognized below. The surname of the first teacher in space, S. Christa McAuliffe, is followed by a symbolic apple.[11]

See also


  1. ^ a b c d "STS-51L Mission Profile". NASA. December 5, 2005. Archived from the original on November 9, 2023. Retrieved December 1, 2023. Public Domain This article incorporates text from this source, which is in the public domain.
  2. ^ Mullane, Mike (2006). Riding Rockets. Simon and Schuster. pp. 204–205. ISBN 9780743276825.
  3. ^ "S. Christa Corrigan McAuliffe" (PDF). Biographical Data. NASA. April 2007. Archived (PDF) from the original on November 27, 2023. Retrieved January 27, 2022. Public Domain This article incorporates text from this source, which is in the public domain.
  4. ^ "STS-51L". Spacefacts. Archived from the original on October 10, 2023. Retrieved February 26, 2014.
  5. ^ "Rogers Commission, Vol. 4 Part. 7". Rogers Commission. Archived from the original on December 8, 2022. Public Domain This article incorporates text from this source, which is in the public domain.
  6. ^ Kerwin, Joseph P. (July 28, 1986). "Challenger Crew Report". NASA. Archived from the original on December 1, 2023. Public Domain This article incorporates text from this source, which is in the public domain.
  7. ^ "Shuttle explodes; crew lost" Daily Leader, Frederick, Oklahoma, January 28, 1986
  8. ^ Isikoff, Michael (March 10, 1986). "Remains of Crew of Shuttle Found". The Washington Post. Archived from the original on November 7, 2012. Retrieved March 5, 2009.
  9. ^ Harwood, William. "The Fate of Challenger's Crew". Archived from the original on May 31, 2023. Retrieved July 24, 2011.
  10. ^ Binkowski, Brooke (February 22, 2001). "Fact Check: Are These the Final Words of the Challenger Crew?". Archived from the original on June 11, 2023. Retrieved December 1, 2023.
  11. ^ Thomas, James A. (Gene) (2006). Some Trust in Chariots: The Space Shuttle Challenger Experience. Xulon Press. p. 197. ISBN 1-60034-096-2.