# Soil Moisture and Ocean Salinity

> ESA Earth observation satellite

**Wikidata**: [Q280068](https://www.wikidata.org/wiki/Q280068)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Soil_Moisture_and_Ocean_Salinity)  
**Source**: https://4ort.xyz/entity/soil-moisture-and-ocean-salinity

## Summary
Soil Moisture and Ocean Salinity (SMOS) is an Earth observation satellite operated by the European Space Agency that measures global soil moisture and ocean salinity from orbit. Launched in 2009, it provides critical data for monitoring water cycles, climate change, and ocean circulation patterns.

## Key Facts
- Soil Moisture and Ocean Salinity is an Earth observation satellite operated by the European Space Agency
- Launched on November 2, 2009, at 01:50:51 from Plesetsk Cosmodrome Site 133
- Weighs 658 kg at launch and 630 kg in dry weight
- Follows a Sun-synchronous orbit at approximately 758-760 km altitude
- Part of the ESA's Living Planet Programme
- Launched on a Rokot vehicle by Eurockot Launch Services
- Powered by two spacecraft solar arrays providing 685 W of power
- Built on the PROTEUS spacecraft bus by Alcatel Space
- Followed by the ADM-Aeolus wind-measuring satellite

## FAQs
### Q: What does the SMOS satellite measure?
A: Soil Moisture and Ocean Salinity (SMOS) specifically measures global soil moisture and ocean salinity from orbit. These measurements are crucial for understanding Earth's water cycle and climate patterns.

### Q: When was SMOS launched and what was its purpose?
A: SMOS was launched on November 2, 2009. Its primary purpose is to provide data on soil moisture and ocean salinity to improve weather forecasting, climate modeling, and monitoring of Earth's water resources.

### Q: What is SMOS's orbital characteristics?
A: SMOS follows a Sun-synchronous orbit at approximately 758-760 km altitude with an orbital inclination of 98.4438 degrees. It has an orbital period of 100.02 minutes and an orbital eccentricity of 0.0001149.

### Q: How long has SMOS been in operation?
A: The provided information does not specify the current operational status of SMOS, but it was launched in 2009 and is still monitoring Earth's soil moisture and ocean salinity as of the latest available data.

### Q: What makes SMOS unique compared to other Earth observation satellites?
A: SMOS is specifically designed to measure soil moisture and ocean salinity using microwave interferometry. It is part of ESA's Living Planet Programme and was followed by ADM-Aeolus, making it part of a specialized Earth observation series.

## Why It Matters
Soil Moisture and Ocean Salinity (SMOS) provides critical data for understanding Earth's water cycle and climate systems. By measuring soil moisture, it helps monitor agricultural conditions, drought situations, and water availability globally. The ocean salinity measurements contribute to understanding ocean circulation patterns, which influence climate and weather systems. This data is essential for improving weather forecasting, climate modeling, and managing water resources effectively. SMOS observations also help researchers track the impacts of climate change on global water cycles and contribute to the scientific community's understanding of Earth's complex environmental systems.

## Notable For
- Specialized design for measuring soil moisture and ocean salinity using microwave interferometry technology
- Part of ESA's Living Planet Programme, focusing on Earth observation missions
- One of the few satellites dedicated specifically to measuring ocean salinity globally
- Built by Alcatel Space on the PROTEUS spacecraft bus
- Launched from Plesetsk Cosmodrome Site 133 on a Rokot launch vehicle with the PROBA-2 satellite

## Body
### Mission Overview
Soil Moisture and Ocean Salinity (SMOS) is an Earth observation satellite operated by the European Space Agency (ESA) that measures global soil moisture and ocean salinity. The satellite is part of ESA's Living Planet Programme and follows ADM-Aeolus in a series of specialized Earth observation missions.

### Technical Specifications
- Mass: 658 kg (launch weight), 630 kg (dry weight)
- Dimensions: 2.4 m height, 2.3 m diameter
- Power: 2 spacecraft solar arrays providing 685 W of power
- Spacecraft bus: PROTEUS
- Manufacturer: Alcatel Space

### Orbital Characteristics
- Orbit type: Sun-synchronous orbit
- Apoapsis: 760.01 km (as of May 4, 2024)
- Periapsis: 758.37 km (as of May 4, 2024)
- Orbital period: 100.02 minutes (as of May 4, 2024)
- Orbital inclination: 98.4438° (as of May 4, 2024)
- Orbital eccentricity: 0.0001149 (as of May 4, 2024)

### Launch Details
- Launch date: November 2, 2009, at 01:50:51
- Launch site: Plesetsk Cosmodrome Site 133
- Launch vehicle: Rokot (vehicle ID: 492-5882-033)
- Launch contractor: Eurockot Launch Services
- Space tug: Briz-KM (ID: 72513)
- Satellite ID: COSPAR ID 2009-059A, NSSDCA ID 2009-059A
- Launch status: Rocket launch with PROBA-2 satellite co-launched

### Mission Status
SMOS is currently operational and continues to provide data on global soil moisture and ocean salinity. It is followed by ADM-Aeolus, which reentered Earth's atmosphere in 2023. The satellite's measurements contribute to weather forecasting, climate modeling, and monitoring of Earth's water resources.

### Data and Applications
The satellite provides critical data for:
- Weather forecasting and climate modeling
- Monitoring agricultural conditions and drought situations
- Tracking ocean circulation patterns
- Understanding global water cycles
- Assessing climate change impacts

### Identifiers and References
- Wikidata ID: 36036
- Website: https://www.esa.int/SMOS
- Wikipedia: Available in multiple languages (ar, ca, commons, de, en, eo, es, fa, fi, fr)
- Wolfram Language entity code: Entity["Satellite", "36036"]
- Gran Enciclopèdia Catalana ID: soil-moisture-and-ocean-salinity

## References

1. [Source](https://space.skyrocket.de/doc_sdat/smos.htm)
2. Jonathan's Space Report
3. [Source](https://space.oscar.wmo.int/satellites/view/smos)
4. Freebase Data Dumps. 2013
5. [Source](https://heavens-above.com/orbit.aspx?satid=36036)