SWARM

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Swarm
Type: Research satellite
(number 3, identical)
Operator: European space agencyESA ESA
COSPAR-ID : 2013-067A / B / C
Mission dates
Dimensions: 468 kg each at the start
Size: 0.75 x 1.30 x 9.00 m
Begin: November 22, 2013, 12:02 UTC
Starting place: Plesetsk (Russia)
Launcher: Rockot
Status: in operation
Orbit data
Rotation time : 93.3 min (Sat. A, C)
94.7 min (Sat. B)
Orbit inclination : 87.3 ° (Sat. A, C)
87.8 ° (Sat. B)
Apogee height :  446 km (Sat. A, C)
511 km (Sat. B)
Perigee height :  443 km (Sat. A, C)
507 km (Sat. B)

Swarm ( English for swarm ) is the name of an ESA satellite mission . The mission is part of the Earth Explorer Missions program and continues the successful CHAMP project. The three identical satellites were launched on November 22, 2013.

mission

The three satellites orbit the earth in the ionosphere in polar orbits . Together they measure the strength, orientation and temporal changes in the earth's magnetic field . From the results, forecasts about the long-term development of the magnetic field should be derived.

The cost of building the satellites was around 86 million euros, and the total cost of the mission was estimated at around 200 million euros. In November 2017, the mission was extended to 2021.

construction

The satellites were manufactured by a German-British team from Airbus Defense and Space in Friedrichshafen . The components are supplied by companies in Europe, for example RUAG Space built the GPS receiver.

The satellites each carry seven instruments for carrying out the project, these are:

  • the Vector Field Magnetometer (VFM), the main scientific instrument of the SWARM mission, measures the vector components of the earth's magnetic field with an accuracy of one nanotesla;
  • the Absolute Scalar Magnetometer (ASM), this is primarily used to calibrate the VFM;
  • the Electric Field Instrument (EFI), equipped with sensors for measuring ion entry angle and velocity;
  • the Accelerometer (ACC), for determining the acceleration of the satellite that was not caused by gravity, such as air resistance and solar wind ;
  • the Laser Range Reflector (LRR), this reflects laser beams from a measuring station on the earth's surface and allows precise distance measurement;
  • the Star Tracker System (STR), this provides extremely precise position data of the satellite and
  • the GNSS Receiver (GPSR), this provides independent real-time information on the position and time of the satellite.

Data products

The Swarm mission provides the following data products for the magnetic field, for the electric field and the ionosphere, as well as for orbit and air resistance. A distinction is made between Level 1b and Level 2 products. Level 1b data are the calibrated time series of the individual satellites, while Level 2 data products are derived from Level 1b data, e.g. T. using the combined satellite measurements (constellation).

Magnetic field
  • Level 1b:
    • Magnetic field strength
    • Magnetic field vector
  • Level 2:
Electric field and ionosphere
  • Level 1b:
    • Electric field vector (EFI)
    • Plasma density
    • Plasma temperature
    • Ion drift velocity (vector)
  • Level 2:
Orbit and drag
  • Level 1b:
    • Air Drag Vector (ACC)
    • Position, location, timestamp (Medium Orbit Determination - MOD)
  • Level 2:

Project office in Germany

From September 2009 to December 2014 there was the Swarm project office at the German Research Center for Geosciences in Potsdam . In cooperation with DLR, it prepared the evaluation of the mission and the use of the Swarm results in various geosciences until the satellites were launched. The coordinator of the German project office was Hermann Lühr, one of the pioneers of the Swarm mission.

Web links

Individual evidence

  1. ↑ a b ESA: Swarm. In: Earth Observation Portal. Retrieved January 5, 2018 .
  2. ↑ Railway data according to SWARM A. N2YO, January 5, 2018, accessed on January 5, 2018 (English). , SWARM B. N2YO, January 5, 2018, accessed January 5, 2018 . , SWARM C. N2YO, January 5, 2018, accessed January 5, 2018 .
  3. ↑ dpa: Satellite trio to research the earth's magnetic field started ( Memento from December 2, 2013 in the Internet Archive ), November 22, 2013
  4. ↑ Deutschlandfunk , Forschung Aktuell , November 22, 2013, Karl Urban : deutschlandfunk.de: Mini swarm explores the terrestrial magnetic field (November 23, 2013)
  5. ↑ [http://www.swarm-projektbuero.de/fileadmin/Dokumente/Satelliten_Steckbrief_Swarm_GFZ.pdf Profile of the GFZ on the Swarm Mission] (link not available)
  6. ↑ ESA: ESA Member States approve Swarm extension. November 20, 2017. Retrieved January 5, 2018 .
  7. ↑ Swarm Technical Annex , April 2004 (PDF, 3.3 MB)
  8. ↑ Data products of the Swarm Mission ( Memento of December 3, 2013 in the Internet Archive ), Project Office Germany
  9. ↑ German Swarm Project Office .
  10. ↑ gfz-potsdam.de: PDF