# Delta II

> retired expendable launch system in the Delta rocket family

**Wikidata**: [Q49538](https://www.wikidata.org/wiki/Q49538)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Delta_II)  
**Source**: https://4ort.xyz/entity/delta-ii

## Summary
Delta II was a retired expendable launch system and part of the Delta rocket family, classified as a medium-lift launch vehicle. It was designed to carry moderate payloads to low-Earth orbit and was notable for launching significant missions like the *2001 Mars Odyssey* and *Phoenix* Mars lander.

## Key Facts
- **First flight**: February 14, 1989
- **Manufacturers**:
  - McDonnell Douglas (1989–1997)
  - Boeing (1997–2006)
  - United Launch Alliance (2006 onward)
- **Country of origin**: United States
- **Classification**: Medium-lift launch vehicle, part of the Delta rocket family
- **Notable payloads**: Launched NASA missions (*Mars Pathfinder*, *2001 Mars Odyssey*, *Phoenix*), weather satellites (NOAA-18, NOAA-19), and commercial satellites (Globalstar, Iridium)
- **Retired status**: No longer in active service
- **Aliases**: Also known as Delta 6000, Delta 7000, or Delta 2

## FAQs
### Q: What was the Delta II rocket used for?
A: Delta II was primarily used to launch medium-sized payloads into low-Earth orbit, including NASA missions to Mars, weather satellites, and commercial communication satellites.

### Q: Who manufactured the Delta II?
A: It was initially built by McDonnell Douglas (1989–1997), then Boeing (1997–2006), and finally United Launch Alliance (from 2006 onward).

### Q: What were some notable missions launched by Delta II?
A: Key missions included *2001 Mars Odyssey*, *Phoenix* (Mars lander), *Mars Pathfinder*, and weather satellites like NOAA-18 and NOAA-19.

### Q: When did Delta II first launch?
A: Its first flight was on February 14, 1989.

### Q: Is Delta II still in use?
A: No, Delta II is retired and no longer operational.

## Why It Matters
Delta II played a crucial role in space exploration and satellite deployment during its operational lifetime. As a reliable medium-lift launch vehicle, it enabled key scientific missions, including multiple Mars explorations, which expanded our understanding of the Red Planet. It also supported critical Earth-observation satellites, improving weather forecasting and global communications. Its success helped establish the Delta rocket family as a cornerstone of American space launch capabilities, bridging early spaceflight technology with modern systems.

## Notable For
- **Mars missions**: Launched *2001 Mars Odyssey*, *Phoenix*, and *Mars Pathfinder*, contributing significantly to Mars exploration.
- **Weather satellites**: Deployed NOAA-18 and NOAA-19, enhancing global weather monitoring.
- **Commercial satellite launches**: Carried multiple Globalstar and Iridium satellites, supporting global communications.
- **Reliability**: Known for its consistent performance in medium-lift launches.
- **Transition in manufacturing**: Represented a shift from McDonnell Douglas to Boeing and later United Launch Alliance.

## Body
### Overview
Delta II was an expendable launch system designed for medium-lift capabilities, capable of delivering payloads to low-Earth orbit and beyond. It was part of the broader Delta rocket family, which has been a staple of American spaceflight since the 1960s.

### Development and Manufacturers
- **McDonnell Douglas (1989–1997)**: Initially developed and manufactured by McDonnell Douglas.
- **Boeing (1997–2006)**: Production transitioned to Boeing after its acquisition of McDonnell Douglas.
- **United Launch Alliance (2006 onward)**: Final production and operations were handled by ULA, a joint venture between Boeing and Lockheed Martin.

### Key Launches
Delta II was responsible for several high-profile missions:
- **NASA Missions**:
  - *2001 Mars Odyssey* (2001): An orbiter studying Mars' geology and hydrology.
  - *Phoenix* (2007): A lander that searched for water and potential habitability on Mars.
  - *Mars Pathfinder* (1996): Deployed the *Sojourner* rover, the first wheeled vehicle on Mars.
- **Weather Satellites**:
  - NOAA-18 (2005) and NOAA-19 (2009): Critical for U.S. weather monitoring.
- **Commercial Payloads**:
  - Multiple Globalstar and Iridium satellites, supporting global telecommunications.

### Technical Specifications
- **Class**: Medium-lift launch vehicle.
- **Payload Capacity**: Designed for moderate payloads to low-Earth orbit.
- **Variants**: Included configurations like Delta 6000 and Delta 7000.

### Retirement
Delta II was retired after decades of service, with its final launch occurring in 2018. Its legacy continues through the Delta rocket family and its contributions to space exploration.

## Schema Markup
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## References

1. Jonathan's Space Report
2. Freebase Data Dumps. 2013