Freja was designed to image the aurora and measure particles and fields in the upper ionosphere and lower magnetosphere.

The mission continued the investigations begun by its predecessor Viking. Freja was initiated in 1987 when a low-cost launch reservation on a Long March rocket for a small store-and-forward low-orbit communications satellite was cancelled. The total cost of the program through 2 years of operations, excluding instruments, was $19 million. The project was jointly financed by Sweden and the Federal Republic of Germany. It made high resolution measurements in the upper ionosphere and lower magnetosphere. Data received at Esrange, Kiruna, Sweden and at the Prince Albert Satellite Station in Canada's Saskatchewan Province.

The spacecraft had a magnesium structure, and a 3-axis magnetometer, sun sensors, and IR earth sensor provided 0.5 deg. attitude knowledge. The satellite was spin stabilized, with its sun-pointing attitude maintained by magnetorquers. Annular solar arrays provided 130 W and recharged NiCd batteries. A 2 W S-band transmitter downlinked at 256 kbps to a 9 m ground-based dish. UHF uplink. The satellite was a prototype development effort.

Payload mass 60 kg and used 81 W. Six radial wire booms (1-15 m) and two stiff radial booms (1-2 m) were used by the experiments. Experiments included:

• F1 - Electric Fields (Royal Inst. of Technology, Sweden)
• F2 - Magnetic Fields (APL/JHU)
• F3C - Cold Plasma (NRC, Canada)
• F3H - Hot Plasma (Swedish Inst. of Space Physics
• F4 - Waves (Swedish Inst. of Space Physics
• F5 - Auroral Imager (Univ. of Calgary)
• F6 - Electron Beam (Max-Planck Inst. )
• F7 - Particle Correlator (Max-Planck Inst. )

Design Life: 2 years. Typical orbit: 601 x 1756 km, 63 deg inclination. Length: 1.70 m (5.50 ft). Maximum Diameter: 2.20 m (7.20 ft). Mass: 259 kg (570 lb). Associated Launch Vehicle: CZ-2C.

• 1992 October 6 - Freja - Launch Site: Jiuquan. Launch Vehicle: CZ-2C.

• 1992 October 6 - Freja - Launch Site: Jiuquan. Launch Vehicle: CZ-2C. Mass: 259 kg (570 lb). Perigee: 590 km (360 mi). Apogee: 1,763 km (1,095 mi). Inclination: 63.00 deg. Period: 108.90 min.

  Ionospheric, auroral, amgnetospheric studies. Freja is a Swedish/German satellite designed for research into the aurora. The satellite was launched piggyback on a Long March 2C (CZ-2C) rocket and weighs 214 kg in orbit. It is a sun-pointing spinner (10 rpm) with a 2.2 m diameter. It will make high re solution measurements in the upper ionosphere and lower magnetosphere. Data will be received at Esrange, Kiruna, Sweden and at the Prince Albert Satellite Station in Canada's Saskatchewan Province. Launch time 0620 UT.

• USAF Satellite Database, USAF Institute of Technology, 1995. Accessed at: ftp://archive.afit.af.mil/pub/space/.

• McDowell, Jonathan, Jonathan's Space Home Page, Harvard University, 1997-present. Jonathan McDowell's complete on-line listing of all objects orbited and over 20,000 rocket launches Accessed at: http://www.planet4589.org/jsr.html.

• Krebs, Gunter, Gunter's Space Page, University of Frankfurt, 1996. Accessed at: http://www.skyrocket.de/space.

• JPL Mission and Spacecraft Library, Jet Propulsion Laboratory, 1997. Accessed at: http://msl.jpl.nasa.gov/home.html.

• McDowell, Jonathan, Launch Log, October 1998. Jonathan McDowell's complete on-line listing of all objects orbited since Sputnik. Accessed at: http://hea-www.harvard.edu/~jcm/space/log/launch.html.