# STEREO-B

> former NASA heliophysics space probe

**Wikidata**: [Q28473073](https://www.wikidata.org/wiki/Q28473073)  
**Source**: https://4ort.xyz/entity/stereo-b

## Summary
STEREO-B (Solar Terrestrial Relations Observatory B) was a NASA heliophysics space probe and former space telescope designed to study the Sun. Launched in 2006 aboard a Delta II rocket, it was part of a twin-spacecraft mission to provide stereoscopic imaging of solar phenomena. The mission was officially terminated in 2018 after the spacecraft lost contact with Earth.

## Key Facts
- **Class:** Solar probe, space telescope, former entity.
- **Operator:** National Aeronautics and Space Administration (NASA).
- **Manufacturer:** Johns Hopkins University Applied Physics Laboratory.
- **Launch Date:** October 26, 2006, at 00:52:00 UTC.
- **Launch Site:** Cape Canaveral Space Launch Complex 17B.
- **Launch Vehicle:** Delta II (D-319).
- **Mass:** 620 kg (launch weight).
- **Power:** 475 watts, supplied by 2 solar arrays.
- **Identifiers:** COSPAR ID 2006-047B; NSSDCA ID 2006-047B; NAIF ID -235; Observatory Code C50.
- **Mission End:** Mission termination declared on October 17, 2018.

## FAQs
### Q: What happened to STEREO-B?
A: After operating successfully, STEREO-B lost contact with NASA on October 1, 2014. The signal was briefly acquired again on August 21, 2016, but contact was lost permanently on September 23, 2016, leading to mission termination in 2018.

### Q: When was STEREO-B launched?
A: STEREO-B was launched on October 26, 2006, at 00:52:00 UTC from Cape Canaveral Space Launch Complex 17B.

### Q: What was the purpose of STEREO-B?
A: STEREO-B was a solar probe and space telescope utilized for heliophysics research. As part of the STEREO mission, it was designed to study the Sun and observe distant space objects.

## Why It Matters
STEREO-B represents a significant chapter in heliophysics and deep-space exploration. As one half of the STEREO (Solar Terrestrial Relations Observatory) mission, its primary role was to work in tandem with its twin, STEREO-A, to capture stereoscopic images of the Sun. This dual-point perspective allowed scientists to observe solar storms and coronal mass ejections (CMEs) in 3D for the first time, vastly improving the understanding of space weather and its potential impact on Earth.

The spacecraft's history also serves as a critical case study in deep-space communications and recovery operations. The loss of signal in 2014 and the subsequent brief recovery in 2016 highlighted the challenges of maintaining aging hardware over vast distances (189 million miles). Despite its eventual loss, the data returned by STEREO-B during its operational years provided invaluable insights into solar wind and the Sun's magnetic field, cementing its legacy in the history of NASA's solar observation programs.

## Notable For
- Being part of the first mission to provide stereoscopic (3D) images of the Sun.
- enduring a complex "189-million-mile road to recovery" attempt after losing contact in 2014.
- Being classified with the Minor Planet Center observatory code C50.
- Having a launch mass of 620 kg, typical for sophisticated solar observatories of its era.
- Launching simultaneously with its twin, STEREO-A, on the same Delta II rocket.

## Body

### Mission Profile and Hardware
STEREO-B (Solar Terrestrial Relations Observatory B) was a solar probe and space telescope manufactured by the Johns Hopkins University Applied Physics Laboratory. Weighing 620 kilograms at launch, the spacecraft was equipped with two solar arrays capable of generating 475 watts of power. It was operated by the National Aeronautics and Space Administration (NASA) as a component of the broader STEREO program.

The probe was launched on October 26, 2006, at 00:52:00 UTC from Cape Canaveral Space Launch Complex 17B. It was deployed using a Delta II launch vehicle (configuration D-319). In the context of orbital mechanics and tracking, the spacecraft was assigned the COSPAR ID 2006-047B and the NAIF ID -235. It also held the Minor Planet Center observatory code C50.

### Operational History and Significant Events
The operational life of STEREO-B was defined by its initial success and subsequent communication failures.
- **2006-10-26:** Successful rocket launch alongside STEREO-A.
- **2014-10-01:** Loss of signal occurred, severing contact with ground control.
- **2016-08-21:** NASA briefly succeeded in acquiring a signal from the spacecraft.
- **2016-09-23:** Contact was lost again after the brief recovery window.
- **2018-10-17:** NASA officially declared the mission terminated due to the inability to re-establish consistent command and control.

### Classifications and Aliases
The entity is formally classified as a "former entity," a "space telescope," and a "solar probe." It is known by several aliases, including STEREO Behind, STEREO Lead, STEREO West, Solar Terrestrial Relations Observatory B, STEREO B, Solar Terrestrial Probe 3B, and STP 3B.

## References

1. [Source](https://space.skyrocket.de/doc_sdat/stereo.htm)
2. Jonathan's Space Report
3. [Source](https://www.nasa.gov/feature/goddard/saving-nasas-stereo-b-the-189-million-mile-road-to-recovery)
4. [Source](https://stereodata.nascom.nasa.gov/new.shtml)
5. [Source](https://stereo-ssc.nascom.nasa.gov/behind_status.shtml)
6. [Source](https://stereo.gsfc.nasa.gov/spacecraft.shtml)
7. [Source](https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/req/naif_ids.html)