# Solar Mesosphere Explorer

> NASA satellite of the Explorer program

**Wikidata**: [Q1394040](https://www.wikidata.org/wiki/Q1394040)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Solar_Mesosphere_Explorer)  
**Source**: https://4ort.xyz/entity/solar-mesosphere-explorer

## Summary
The Solar Mesosphere Explorer (SME) was a NASA satellite launched in 1981 as part of the Explorer program. It was designed to study the Earth's mesosphere and lower thermosphere, providing critical data on atmospheric composition and dynamics. The mission ended in 1991 when the satellite re-entered the atmosphere.

## Key Facts
- **Launch Date**: October 6, 1981
- **Operator**: National Aeronautics and Space Administration (NASA)
- **Manufacturer**: Jet Propulsion Laboratory (JPL)
- **Launch Vehicle**: Delta 2000
- **Launch Site**: Vandenberg Space Launch Complex 2
- **Orbit Decay**: March 5, 1991
- **Classification**: Earth observation satellite
- **COSPAR ID**: 1981-100A
- **NSSDCA ID**: 1981-100A
- **Aliases**: Explorer 64

## FAQs
### Q: What was the purpose of the Solar Mesosphere Explorer?
A: The SME was designed to study the Earth's mesosphere and lower thermosphere, focusing on atmospheric composition and dynamics.

### Q: Who operated the Solar Mesosphere Explorer?
A: The satellite was operated by NASA, with the Jet Propulsion Laboratory (JPL) responsible for its manufacture.

### Q: When was the Solar Mesosphere Explorer launched?
A: The satellite was launched on October 6, 1981, from Vandenberg Space Launch Complex 2.

### Q: What was the launch vehicle for the Solar Mesosphere Explorer?
A: The satellite was launched using the Delta 2000 rocket.

### Q: When did the Solar Mesosphere Explorer mission end?
A: The mission ended in March 1991 when the satellite re-entered the atmosphere.

## Why It Matters
The Solar Mesosphere Explorer played a crucial role in advancing our understanding of the Earth's mesosphere and lower thermosphere. By providing detailed data on atmospheric composition and dynamics, the SME contributed to scientific research on atmospheric processes, including the behavior of ozone and other trace gases. Its observations helped improve models of atmospheric circulation and energy balance, enhancing our knowledge of climate and weather patterns. The mission also demonstrated the capabilities of small, dedicated satellites in Earth observation, paving the way for future atmospheric research.

## Notable For
- **First-of-its-kind atmospheric studies**: The SME was one of the first satellites to focus specifically on the mesosphere and lower thermosphere.
- **Contribution to atmospheric science**: Its data improved understanding of atmospheric composition and dynamics.
- **Use of the Delta 2000 launch vehicle**: The mission marked an early use of the Delta 2000 rocket for scientific payloads.
- **Long-duration mission**: The satellite operated successfully for nearly a decade before re-entering the atmosphere.

## Body
### Mission Overview
The Solar Mesosphere Explorer (SME) was a NASA satellite launched on October 6, 1981, as part of the Explorer program. It was designed to study the Earth's mesosphere and lower thermosphere, providing critical data on atmospheric composition and dynamics. The mission ended in March 1991 when the satellite re-entered the atmosphere.

### Technical Specifications
- **Operator**: National Aeronautics and Space Administration (NASA)
- **Manufacturer**: Jet Propulsion Laboratory (JPL)
- **Launch Vehicle**: Delta 2000
- **Launch Site**: Vandenberg Space Launch Complex 2
- **Orbit Decay**: March 5, 1991

### Scientific Contributions
The SME contributed significantly to atmospheric science by providing detailed observations of the mesosphere and lower thermosphere. Its data improved models of atmospheric circulation and energy balance, enhancing our understanding of climate and weather patterns. The mission also demonstrated the effectiveness of small, dedicated satellites in Earth observation.

### Legacy
The Solar Mesosphere Explorer remains a notable achievement in atmospheric research, showcasing the capabilities of small satellites in advancing scientific knowledge. Its legacy continues to influence current and future missions focused on atmospheric studies.

## References

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