The SMOS (Soil Moisture and Ocean Salinity) programme, the second Earth Explorer Opportunity mission selected under ESA’s Living Planet programme, has been designed to observe and monitor two important variables of the Earth’s climate system – soil moisture over landmasses and salinity over the oceans. These two parameters are of key interest as they are fundamental for understanding the planet’s global water cycle, and thus for the creation of atmospheric, oceanographic and hydrological prediction models.
Astrium Spain designed and built the SMOS mission’s single-instrument payload and the innovative two-dimensional interferometer MIRAS (Microwave Imaging Radiometer using Aperture Synthesis). A real technological challenge, it employs measuring techniques that have never before been used in space. From a scientific, technological and industrial point of view, MIRAS is the most significant programme developed for ESA in Spain to date.
The SMOS satellite was launched on a Rockot vehicle from the Russian Plesetsk Cosmodrome in November 2009.
Fact Sheet
| Customer | European Space Agency |
| Mission | To measure soil moisture over land & salinity over oceans |
| Orbit | Sun-synchronous, dawn/dusk, quasi-circular orbit at altitude 758km. 06.00 hrs local solar time at ascending node |
| Spacecraft | Lead by Thales Alenia Space Industries. A Proteus platform adapted to the needs of the SMOS mission |
| Payload | Lead by Astrium Spain. MIRAS - Microwave Imaging Radiometer using Aperture Synthesis (Passive microwave 2D-interferometer) |
| Features | • Frequency: L-band • Number of receivers: 69 • Receiver spacing: 18.37cm • Polarisation: H & V (polarimetric mode optional) • Spatial resolution: 35km at centre of field of view • Tilt angle: 32.5 degrees • Radiometric resolution: 0.8 - 2.2K • Angular range: 0-55 degrees • Instrument data rate: 89kbps H & V pol |
| Launch Mass | 658 kg (platform 275 kg, payload 355 kg, fuel 28 kg) |
| Dimensions | Cylinder 2.4m high and 2.3m in diameter |
| Launch Date | 2009 |
| Mission Duration | Three years (including a six-month commissioning phase) with a possible two-year extension |
| Astrium Responsibilities | Payload Prime & MIRAS Instrument |
