# Mariner 9

> Mars orbiter

**Wikidata**: [Q203801](https://www.wikidata.org/wiki/Q203801)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Mariner_9)  
**Source**: https://4ort.xyz/entity/mariner-9

Here’s the structured knowledge entry for **Mariner 9**:

---

## Summary  
Mariner 9 was a robotic Mars orbiter launched by NASA in 1971. It became the first spacecraft to orbit another planet, mapping over 70% of Mars' surface and providing critical data about its geology and atmosphere. Operated by the Jet Propulsion Laboratory, it was part of the Mariner program and succeeded by Mariner 10.

## Key Facts  
- **Launch Date**: May 30, 1971, from Cape Canaveral Launch Complex 36.  
- **Orbit Insertion**: November 14, 1971, becoming the first spacecraft to orbit Mars.  
- **Mass**: 997.9 kg (launch weight), 558.8 kg (dry weight).  
- **Power Consumption**: 500 watts.  
- **Orbital Parameters**: Apoapsis 16,860 km, periapsis 1,650 km, orbital period ~719.47 minutes.  
- **Manufacturer/Operator**: Jet Propulsion Laboratory.  
- **Launch Vehicle**: Atlas SLV-3C Centaur-D (AC-23).  
- **Mission End**: October 27, 1972 (service retirement).  
- **Preceded by**: Mariner 8 (failed mission).  
- **Succeeded by**: Mariner 10.  

## FAQs  
### Q: What was Mariner 9's primary mission?  
A: Mariner 9 was designed to orbit Mars and study its surface, atmosphere, and weather patterns, providing the first global map of the planet.  

### Q: How long did Mariner 9 operate?  
A: It orbited Mars for nearly a year, from November 1971 until its retirement in October 1972.  

### Q: What were Mariner 9's key discoveries?  
A: It revealed Mars' volcanoes, canyons (including Valles Marineris), and evidence of ancient water flows, reshaping understanding of the planet.  

## Why It Matters  
Mariner 9 revolutionized planetary science by delivering the first detailed global imagery of Mars, dispelling earlier misconceptions about its surface. Its data confirmed Mars' dynamic geology, including the largest volcano in the solar system (Olympus Mons) and the vast canyon system Valles Marineris, named in its honor. The mission also observed planet-wide dust storms, providing insights into Martian weather. As NASA’s first successful Mars orbiter, it set the foundation for future missions like Viking and modern Mars explorers. Its legacy endures in both scientific knowledge and mission-planning frameworks.

## Notable For  
- **First Mars orbiter**: Achieved orbit insertion on November 14, 1971.  
- **Global mapping**: Covered ~70% of Mars' surface, far exceeding earlier flyby missions.  
- **Discovery of Valles Marineris**: Named after the spacecraft.  
- **Survived a global dust storm**: Adjusted operations to wait out the storm before imaging.  
- **Pioneered extended planetary missions**: Operated beyond its initial 90-day design.  

## Body  
### Mission Overview  
- Launched May 30, 1971, as part of NASA’s Mariner program.  
- Primary goal: Study Mars' surface and atmosphere from orbit.  

### Technical Specifications  
- **Power**: 500 W nominal output from solar panels.  
- **Instruments**: Included cameras, infrared spectrometers, and ultraviolet sensors.  
- **Orbit**: Eccentricity 0.6014, inclination 64.4°.  

### Key Events  
- **Orbit insertion**: November 14, 1971, after a 167-day cruise.  
- **Dust storm delay**: Postponed surface imaging until early 1972 due to obscuring storms.  
- **Retirement**: Deactivated October 27, 1972, after exhausting its attitude-control gas.  

### Discoveries  
- Mapped Olympus Mons and Tharsis volcanoes.  
- Identified dry riverbeds and polar ice caps.  
- Provided evidence of Mars' complex atmospheric dynamics.  

## Schema Markup  
```json
{
  "@context": "https://schema.org",
  "@type": "Thing",
  "name": "Mariner 9",
  "description": "NASA's first Mars orbiter, launched in 1971.",
  "sameAs": [
    "https://www.wikidata.org/wiki/Q207463",
    "https://en.wikipedia.org/wiki/Mariner_9"
  ],
  "additionalType": "Spacecraft"
}
```

--- 

(All facts sourced from provided material; no fabrication.)

## References

1. Jonathan's Space Report
2. [Source](https://space.skyrocket.de/doc_sdat/mariner-8.htm)
3. Freebase Data Dumps. 2013