FREJA

Artist's impression of Freja in space

Freja is a Swedish-German satellite for the detailed exploration of the topside ionosphere and lower magnetosphere. It was launched on October 6, 1992, on a Chinese Long March rocket. The main phase of the data acquistion ended in June 30, 1995, but the satellite was alive and took some data up to mid-October 1996, when it finally stopped after an excellent record of four years of operations.

[Freja mockup] The Freja mockup now is placed in the entrance hall at the Swedish Space Corporation. More pictures here!

Scientific instruments

There were several scientific instruments onboard Freja, numbered F1 to F7. We at the Uppsala Division of the Swedish Institute of Space Physics had PI responsibility for the Freja Wave and Plasma Density Instrument (F4). Pages with information on the other Freja instruments, in some cases with data and results, are given here:

F1 electric field instrument (KTH, Stockholm)
F2 magnetometer (APL, Baltimore)
F3H hot plasma instrument (IRF, Kiruna)
F3C cold plasma analyzer (HIA/NRC, Ottawa/University of Calgary)
F4 wave and plasma density instrument (IRF, Uppsala)
F5 auroral imager (University of Calgary)
F6 electron beam instrument (MPI, Garching)
F7 electron spectrometer (MPI, Garching)

Freja operations

The operations of Freja, particularly what regards the F4 instrument, is documented here. This is rather technical information, useful only if you are familiar with the Freja instruments.

Other nice Freja links

Freja summary plots - Summary of the scientific data from the eight Freja instruments, available at APL, Baltimore.
F3H Data Archive - Particle data from the TICS ion spectrometer and the MATE electron spectrometer, at IRF Kiruna, Sweden.
Present location of Freja (from KTH, Stockholm)
The Freja satellite - A brief description of the spacecraft at the Swedish Space Corporation, Solna.

To IRF-U space plasma physics programme
To IRF-U home page

Swedish Institute of Space Physics
Uppsala Division

http://www.space.irfu.se/freja/index.html
Page maintained by Anders Eriksson
Latest update 020614