Viking was

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

's first

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ...

. It was launched on an

Ariane 1 Ariane 1 was the first rocket in the Ariane family of expendable launch systems. It was developed and operated by the European Space Agency (ESA), which had been formed in 1973, the same year that development of the launcher had commenced. A ...

rocket as a piggyback payload together with the French satellite SPOT 1, on February 22, 1986. Operations ended on May 12, 1987. Viking was used to explore plasma processes in the magnetosphere and the ionosphere.

Spacecraft

Space was limited underneath the SPOT 1 satellite, and Viking had to be quite sturdy in order to withstand the stress of launch. The basic shape of the Swedish satellite was a flat octagonal disc, 0.5 metres thick and 1.9 metres across. The mechanical interface of the

payload Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...

adapter from the Ariane rocket was duplicated on top of Viking. This enabled it to be added to the launch with a minimum of redesign of the SPOT satellite. After SPOT had been released, Viking fired its own

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accordanc ...

and was sent into its proper

polar orbit A polar orbit is one in which a satellite passes above or nearly above both poles of the body being orbited (usually a planet such as the Earth, but possibly another body such as the Moon or Sun) on each revolution. It has an inclination of about ...

Mission

Once in orbit, 4

wire Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is c ...

segments of 40 metre length each were spooled out in a radial direction from the edge of the spinning satellite disc. Also, 2 stiff rods of 4 metre length were extended in the axial direction. A sensor pod was stationed at the end of each of these, forming three orthogonal pairs. Together they could measure the

electric field An electric field (sometimes E-field) is the physical field that surrounds electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to the physical field fo ...

of the earth in all three dimensions. Stiff booms were also extended for other types of sensors and antennas. The mission produced a large amount of extremely useful scientific data, and was deemed a great success. An initial discussion of what scientists learned from these measurements, which included "global distribution of magnetosphere-ionosphere interaction;

aurora An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of bri ...

l morphology and substorm dynamics; heating and expulsion of ionospheric plasma into the magnetosphere; field aligned acceleration into the ionosphere; and electron and ion wave generation"Scientific results from the Swedish Viking satellite
Hultqvist, Bengt. Status Report, 1988 Swedish Inst. of Space Physics, Kiruna. can be found in the article "Scientific results from the Swedish Viking satellite", 1988 Swedish Inst. of Space Physics, Kiruna. Since then, many other scientific articles have been written using this important data set.

Post mission

After the scientific mission ended, both ''Viking'' and the upper stage of the rocket used to launch the satellite became derelict

objects Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an ...

that would continue to orbit Earth for many years. , both objects remain in orbit.

References

External links

Viking information at NSSDC Master Catalog
{{Orbital launches in 1986 Derelict satellites orbiting Earth Geospace monitoring satellites Space programme of Sweden First artificial satellites of a country Spacecraft launched in 1986