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Viking Sweden



Viking Sweden, the first Swedish national satellite, was a polar-orbiting research satellite for exploration of magnetospheric phenomena which take place in the altitude range of 1-2 earth radii above the auroral zones. The objective of the mission was to investigate the interactions between the hot collisionless plasmas and the cold collisionless plasmas on auroral zone magnetic field lines and to relate these processes to the detailed auroral characteristics. To investigate these phenomena, Viking Sweden was instrumented for simultaneous in situ measurements of fields, particles, plasmas, and waves. In addition, an ultraviolet imager recorded the auroras. The payload instruments measured the following: the electrostatic vector field, the geomagnetic vector field, the cold plasma density, the hot plasma distribution function from 1 eV to 300 keV energy, the hot ion composition, all three components of electric waves of frequencies up to 500 kHz, magnetic waves of frequencies up to 10 kHz, and ultraviolet images of auroral forms.

Coordinated observations from sounding rockets and with ground-based facilities such as EISCAT provided important complementary data. The Viking Sweden satellite was launched together with the French remote sensing satellite SPOT, a project in which Sweden participates. Initially, Viking Sweden was placed in the same orbit as SPOT, but it was injected into its final orbit by means of a separate boost motor.

The main body of the spacecraft had a flat octagonal shape, 0.5 m high and with a diagonal of 1.8 m. For the wave and electric measurements there were three probe pairs, one axial probe pair 8 m tip-to-tip and two orthogonal radial pairs on wire booms 80 m tip-to-tip. There were also extendable booms for the magnetometer, and a loop antenna. The satellite was spin-stabilized at 3 rpm, with the spin axis perpendicular to the orbital plane. The spin-axis direction was controlled to within 5 degrees, and was determined afterwards to be better than 1 degree accuracy. Magnetic torquing was used for attitude and spin control, and thermal control was passive. Power was provided by 2.2 sq m of solar cells on the satellite body. The design lifetime was eight months, although the lifetime in orbit will be far greater than that. Operations ceased on 12 May 1987.

Alternate Names

  • 16614
  • Viking
  • VikingSweden
  • viking

Facts in Brief

Launch Date: 1986-02-22
Launch Vehicle: Ariane
Launch Site: Kourou, French Guiana
Mass: 535 kg
Nominal Power: 80 W

Funding Agency

  • Swedish Board for Space Activities (Sweden)


  • Space Physics

Additional Information

Questions and comments about this spacecraft can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Mr. P. ZetterquistProject ManagerSwedish Space Corporation
Dr. Kerstin FredgaProject ScientistSwedish Board for Space Activities
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