# Challenger

> American Space Shuttle orbiter

**Wikidata**: [Q54382](https://www.wikidata.org/wiki/Q54382)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Space_Shuttle_Challenger)  
**Source**: https://4ort.xyz/entity/challenger

## Summary
Challenger (OV-099) was a NASA Space Shuttle orbiter manufactured by Rockwell International, designed to carry humans and cargo into low Earth orbit. It served as the second operational orbiter in the Space Shuttle program, flying 10 missions between 1983 and 1986. The vehicle was destroyed during launch on January 28, 1986, during the STS-51-L mission.

## Key Facts
- **Type**: Space Shuttle orbiter (reusable spaceplane)
- **Operator/Owner**: National Aeronautics and Space Administration (NASA)
- **Manufacturer**: Rockwell International
- **Designation**: OV-099 (originally STA-099 as a Structural Test Article)
- **Named After**: HMS Challenger
- **Dimensions**:
  - Length: 37.24 meters
  - Height: 17.25 meters
  - Wingspan: 23.79 meters
  - Empty Weight (rollout): 70,488 kilograms; (with RS-25 engines): 79,415 kilograms
- **First Flight**: April 4, 1983 (STS-6)
- **Last Flight**: January 28, 1986 (STS-51-L)
- **Total Missions**: 10
- **Total Orbits Completed**: 995
- **Total Distance Traveled**: 41,527,409.6 kilometers
- **Total Mission Duration**: 5,385,382 seconds (approximately 62.3 days)
- **Satellites Deployed**: 10
- **Construction Location**: Air Force Plant 42
- **Delivery Date**: July 5, 1982
- **End of Service**: Destroyed during launch failure on January 28, 1986

## FAQs

### Q: What was Challenger's role in the Space Shuttle program?
Challenger was the second operational Space Shuttle orbiter, used to transport astronauts and cargo to low Earth orbit. It conducted 10 missions, deploying satellites and supporting scientific research.

### Q: How did Challenger differ from other Space Shuttle orbiters?
Challenger was originally built as a Structural Test Article (STA-099) before being converted into an operational orbiter (OV-099) between 1979 and 1981. It was lighter than Columbia and designed for higher flight rates.

### Q: What caused the loss of Challenger?
Challenger was destroyed 73 seconds after liftoff on January 28, 1986, during mission STS-51-L, due to a launch failure involving the solid rocket booster O-ring seals in cold weather conditions.

### Q: What notable missions did Challenger fly?
Challenger's first mission, STS-6 (April 4, 1983), deployed the first Tracking and Data Relay Satellite. The orbiter also conducted the first shuttle night launch and night landing during its operational lifetime.

### Q: When was Challenger built and delivered?
Challenger's construction began on November 21, 1975, and was completed on February 10, 1978. It was delivered to NASA's Kennedy Space Center on July 5, 1982, after conversion from test article to operational orbiter.

### Q: What happened to Challenger's remains?
Debris from Challenger was recovered from the Atlantic Ocean following the 1986 disaster. The remains are stored in a sealed silo at Cape Canaveral Space Force Station and are not publicly displayed.

## Why It Matters
Challenger represents a critical chapter in the history of human spaceflight, embodying both the ambitions and risks of space exploration. As NASA's second operational orbiter, it enabled the agency to increase flight frequency and expand the Shuttle program's capabilities. Its missions contributed to satellite deployment, scientific research, and the early foundations of International Space Station planning.

The loss of Challenger on January 28, 1986, fundamentally transformed NASA's approach to safety and engineering culture. The disaster led to the creation of the Rogers Commission investigation, resulting in major reforms in NASA's management practices, engineering oversight, and safety protocols. These changes influenced all subsequent human spaceflight programs, including the redesign of solid rocket boosters and the establishment of more rigorous launch commit criteria.

The orbiter's legacy extends beyond its operational achievements. The lessons learned from the Challenger accident continue to inform aerospace engineering, risk management, and organizational decision-making across the global space industry. Its story serves as a case study in complex system failures and the importance of addressing technical concerns raised by engineers.

## Notable For
- **Second Operational Orbiter**: Challenger was the second Space Shuttle orbiter to fly in space after Columbia.
- **Converted Test Article**: Originally built as STA-099 for structural testing before conversion to OV-099.
- **First Shuttle Night Launch and Landing**: Achieved during its operational missions.
- **Deployed 10 Satellites**: Contributed significantly to communications and tracking infrastructure.
- **First Tracking and Data Relay Satellite Deployment**: STS-6 mission deployed TDRS-1.
- **Tragic Loss**: Destroyed 73 seconds after launch on January 28, 1986, resulting in the deaths of all seven crew members.
- **Catalyst for Safety Reform**: The disaster prompted comprehensive changes to NASA's safety culture and engineering practices.
- **High Flight Rate Design**: Built for more frequent missions than earlier orbiters.

## Body

### Design and Specifications
Challenger was designed as a reusable winged spacecraft capable of vertical launch and horizontal landing. The orbiter featured an aluminum airframe protected by thermal insulation for atmospheric re-entry.

- **Structural Configuration**: Aluminum airframe with thermal protection system
- **Propulsion**: Three RS-25 liquid-fueled main engines (each producing approximately 1.8 MN thrust at liftoff); two Orbital Maneuvering System engines
- **Crew Capacity**: 5–7 astronauts
- **Payload Capacity**: Up to 24,400 kilograms to low Earth orbit

The orbiter's design emphasized weight reduction compared to Columbia, allowing for increased payload capacity and improved performance for frequent flight operations.

### Construction and Conversion
Challenger's development followed a unique path compared to other orbiters:

- **Contract Award (STA-099)**: July 26, 1972, to North American Rockwell
- **Construction Period**: November 21, 1975, to February 10, 1978, at Air Force Plant 42
- **Rollout (as STA-099)**: February 14, 1978
- **Mechanical Testing**: 1978–1979
- **Contract Award (OV-099 Conversion)**: January 1, 1979
- **Conversion to Operational Orbiter**: January 28, 1979, to October 21, 1981, at Air Force Plant 42
- **Rollout (as OV-099)**: June 30, 1982
- **Delivery to Kennedy Space Center**: July 5, 1982

The conversion from structural test article to flight vehicle allowed NASA to accelerate orbiter availability while utilizing existing airframe investments.

### Operational History
Challenger began operational service with its maiden flight on April 4, 1983, designated STS-6.

**Mission Statistics**:
- **Total Missions**: 10
- **Total Orbits**: 995
- **Total Distance**: 41,527,409.6 kilometers
- **Total Duration**: 5,385,382 seconds

**Key Missions**:
- **STS-6 (April 4, 1983)**: Maiden flight; deployed first Tracking and Data Relay Satellite (TDRS-1)
- **STS-7 (June 18, 1983)**: Featured Sally Ride, the first American woman in space
- **STS-8 (August 30, 1983)**: First night launch and night landing of a Space Shuttle
- **STS-41B (February 3, 1984)**: Featured first untethered spacewalk using the Manned Maneuvering Unit
- **STS-41C (April 6, 1984)**: First satellite repair mission (Solar Maximum Mission)
- **STS-41G (October 5, 1984)**: Included Kathryn Sullivan, first American woman to perform a spacewalk

**Satellite Deployments**:
Challenger deployed 10 artificial satellites across its missions, including communications satellites and the Tracking and Data Relay Satellite system.

### Final Mission and Loss
On January 28, 1986, Challenger launched on its tenth mission, STS-51-L. The mission was designated to deploy the second Tracking and Data Relay Satellite and carry the SPARTAN-203 Halley's Comet observer.

**Crew of STS-51-L**:
- Francis R. Scobee, Commander
- Michael J. Smith, Pilot
- Ronald McNair, Mission Specialist
- Ellison Onizuka, Mission Specialist
- Judith Resnik, Mission Specialist
- Gregory Jarvis, Payload Specialist
- Christa McAuliffe, Payload Specialist (Teacher in Space Project)

The launch failure occurred 73 seconds after liftoff, resulting from the failure of an O-ring seal in the right solid rocket booster. Cold weather conditions at launch contributed to the seal's degradation, allowing hot gases to escape and compromise the external tank. The resulting structural breakup destroyed the orbiter and claimed all seven crew members.

### Aftermath and Legacy
The loss of Challenger led to a 32-month suspension of the Space Shuttle program while investigations and redesigns were conducted. The Rogers Commission, chaired by former Secretary of State William Rogers, identified both technical failures and organizational issues within NASA as contributing factors.

**Key Reforms Following the Disaster**:
- Redesign of solid rocket booster joints with improved seals and heating systems
- Establishment of stricter launch commit criteria, including temperature limits
- Enhanced safety oversight and improved communication channels for engineer concerns
- Creation of the Office of Safety, Reliability, and Quality Assurance

### Related Entities and Connections
- **Parent Program**: Space Shuttle program (operated 1981–2011)
- **Manufacturer**: Rockwell International
- **Operator**: National Aeronautics and Space Administration (NASA)
- **Sister Orbiters**: Enterprise (test vehicle), Columbia, Discovery, Atlantis, Endeavour (built to replace Challenger)
- **Named After**: HMS Challenger, a British corvette known for its oceanographic expedition (1872–1876)

### Identifiers and Designations
- **Orbiter Vehicle Designation**: OV-099
- **Original Designation**: STA-099 (Structural Test Article)
- **Serial Numbers**: STA-099 (1972–1978); OV-099 (1979–1986)

### Alternate Names and Aliases
Challenger is known by various names and designations across different languages and reference systems, including:
- OV-099, OV099, Orbiter Vehicle 99
- Space Shuttle Challenger
- Challenger (navette spatiale) [French]
- Challenger (Raumfähre) [German]
- スペースシャトル・チャレンジャー [Japanese]
- 挑战者号航天飞机 [Chinese]
- Челленджер (шаттл) [Russian]
- Challenger (ônibus espacial) [Portuguese]
- تشالنجر (مكوك فضاء) [Arabic]

## References

1. [Source](https://www.nasa.gov/pdf/566250main_SHUTTLE%20ERA%20FACTS_040412.pdf)
2. [Source](https://www.latimes.com/business/la-xpm-2011-jul-05-la-fi-shuttle-legacy-20110705-story.html)
3. Virtual International Authority File
4. [Source](https://www.nasa.gov/centers/kennedy/shuttleoperations/orbiters/challenger-info.html)
5. Freebase Data Dumps. 2013
6. [Source](https://spaceflightnow.com/shuttle/features/000414overhaul/birthplace.html)
7. [Source](https://www.nasaspaceflight.com/2011/01/1983-1986-missions-history-space-shuttle-challenger/)
8. [Source](https://www.nasa.gov/sites/default/files/files/1.pdf)
9. BBC Things
10. [Source](https://history.nasa.gov/SP-4225/diagrams/shuttle/shuttle-diagram-4.htm)
11. [Source](http://www.cbsnews.com/network/news/space/129/129quicklook2.pdf)
12. [Source](http://www.astronautix.com/c/challenger.html)
13. Quora
14. KBpedia