# Mars Global Surveyor

> US spacecraft developed by NASA's Jet Propulsion Laboratory

**Wikidata**: [Q206300](https://www.wikidata.org/wiki/Q206300)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Mars_Global_Surveyor)  
**Source**: https://4ort.xyz/entity/mars-global-surveyor

## Summary
Mars Global Surveyor (MGS) was a U.S. spacecraft developed by NASA's Jet Propulsion Laboratory to study Mars from orbit. Launched in 1996, it became one of the most successful missions in Mars exploration history, operating until 2006.

## Key Facts
- **Launched:** November 7, 1996, from Cape Canaveral Space Launch Complex 17  
- **Developer:** Jet Propulsion Laboratory (JPL)  
- **Operator:** National Aeronautics and Space Administration (NASA)  
- **Launch Vehicle:** Delta II  
- **Mass:** 1,030 kilograms  
- **Orbital Period:** 1.95 hours around Mars  
- **Mission End:** November 2, 2006 due to loss of signal caused by technical failure  
- **Part Of:** Mars Exploration Program  
- **Aliases:** MGS, 火星全球勘測者, マーズ・グローバル・サーベイヤー  

## FAQs
### Q: What was the purpose of the Mars Global Surveyor mission?
A: The Mars Global Surveyor was designed to map the surface, study the atmosphere, and analyze the gravitational and magnetic fields of Mars from orbit. Its goal was to provide comprehensive global data to better understand the planet’s geology and climate.

### Q: How long did Mars Global Surveyor operate?
A: Mars Global Surveyor operated for nearly 10 years. It entered orbit around Mars on September 11, 1997, and ceased operations on November 2, 2006, after losing contact with Earth.

### Q: What were some major discoveries made by Mars Global Surveyor?
A: MGS discovered evidence of past water activity on Mars, mapped the planet's topography and gravity field in detail, and identified changes in gullies suggesting recent geological activity. It also helped confirm the presence of a residual magnetic field in Mars’ crust.

## Why It Matters
The Mars Global Surveyor fundamentally transformed our understanding of Mars. As the first successful interplanetary orbiter since the Viking missions in the 1970s, it laid the groundwork for future Mars exploration. Over its decade-long mission, it returned more than 240,000 images and vast datasets that informed subsequent missions like the Mars Reconnaissance Orbiter. Its findings reshaped scientific views on Martian geology, climate evolution, and potential for past habitability, making it a cornerstone of planetary science.

## Notable For
- First successful return-to-orbit mission at Mars since Viking  
- Longest-operating Mars orbiter at the time of its retirement  
- Discovery of recurring slope lineae and possible signs of recent liquid water activity  
- High-resolution mapping of Martian topography and gravity field  
- Pioneering use of aerobraking to achieve final orbital configuration  

## Body

### Mission Overview
Mars Global Surveyor (MGS) was launched on November 7, 1996, aboard a Delta II rocket from Cape Canaveral Air Force Station. Developed by NASA's Jet Propulsion Laboratory, the mission aimed to conduct detailed studies of Mars' surface, atmosphere, and internal structure through orbital reconnaissance.

After a 10-month journey, MGS successfully entered orbit around Mars on September 11, 1997. Using aerobraking techniques over several months, it adjusted its highly elliptical capture orbit into a near-circular polar orbit suitable for scientific observations.

### Technical Specifications
- **Spacecraft Mass:** 1,030 kg  
- **Power Output:** 980 watts (nominal)  
- **Orbit Characteristics:**  
  - Periapsis: 372.8 km  
  - Apoapsis: 436.5 km  
  - Inclination: 92.9°  
  - Eccentricity: 0.008  
  - Semi-major axis: 3,769 km  
  - Orbital period: ~1.95 hours  

### Instruments
MGS carried five primary instruments:
- **Mars Orbiter Camera (MOC)** – Provided high-resolution imaging of the Martian surface  
- **Thermal Emission Spectrometer (TES)** – Studied mineral composition and atmospheric temperature  
- **Mars Orbiter Laser Altimeter (MOLA)** – Measured precise elevations across the planet  
- **Magnetometer/Electron Reflectometer (MAG/ER)** – Detected remnant magnetism in the Martian crust  
- **Radio Science Experiment (RS)** – Analyzed atmospheric properties and gravity field variations  

### Scientific Contributions
During its operational lifetime, MGS revolutionized knowledge of Mars:
- Created the first complete global map of Martian topography using laser altimetry  
- Identified layered sedimentary deposits indicating ancient lake beds or oceans  
- Observed seasonal dust storms and polar ice cap dynamics  
- Discovered subtle changes in surface features interpreted as evidence of recent water flow  
- Found patterns of remnant magnetism suggesting early dynamo activity in Mars’ core  

### Mission Conclusion
Contact with MGS was lost on November 2, 2006, following an unexpected attitude control anomaly during a routine maneuver. Despite efforts to reestablish communication, the mission officially ended later that month. The spacecraft had exceeded all design expectations, operating for nearly ten years—more than four times its planned duration.

### Legacy
Mars Global Surveyor set new standards for interplanetary robotic exploration. Its legacy includes foundational datasets still used today, influence on landing site selection for rovers such as Spirit and Opportunity, and establishment of JPL’s approach to long-term planetary orbital missions.

## References

1. Jonathan's Space Report
2. Freebase Data Dumps. 2013
3. [Source](https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/req/naif_ids.html)
4. KBpedia