Sweden's first satellite, Viking, was launched 40 years ago
And KTH was deeply involved...
Sweden's first satellite, Viking, was launched with an Ariane rocket from Kourou in French Guiana on 22 February 1986. The satellite explored the Earth's magnetosphere at altitudes of up to 13500 km, i.e. about an Earth's diameter. Swedish space plasma researchers from KTH, and the Institute of Space Physics in Kiruna and Uppsala were deeply involved in the project and its scientific instruments.
The project was managed by the Swedish Space Corporation (now called SSC Space) and the satellite was developed by Saab in Linköping and Boeing Aerospace in Seattle in collaboration. The original idea for Viking was sparked by Professor Bengt Hultqvist at the Institute of Space Physics in Kiruna. Project manager at the Swedish Space Company in Solna during the satellite's early development phase was M.Sc. Per Zetterquist (M.Sc. KTH, EE).
The scientific mission for Viking was formulated through in-depth discussions between the Swedish research groups and their foreign colleagues. An important meeting was held in December 1977 in Hannes Alfvén's office (Professor Alfvén was temporarily away) at KTH on floor 5 at Teknikringen 31, recalls Sven Grahn (M.Sc, KTH, 1969), senior researcher at KTH Space Center: "We were three young engineers (all KTH students), from the Swedish Space Company who carefully took notes of what the researchers wanted," Sven recalls.
It was the beginning of a long collaboration between Swedish and foreign researchers, the Swedish Space Corporation's project management, engineers at Saab and Boeing, many subcontractors and not least the French space agency CNES[1], who agreed to launch Viking together with their Earth observation satellite SPOT on board the European rocket Ariane.
Viking was built as an octagonal disc with a diameter of 1.9 meters and a height of about 0.5 meters. It weighed 286 kg on site in space. It rotated around the axis of the "disc" at 3 revolutions per minute. The rotation allowed sensors for the electric field to be kept at a distance of 40 meters from the satellite body. Sensors for the magnetic field and electromagnetic waves were mounted on shorter booms. The rotation also allowed detectors for charged particles to sweep the revolution around up and down along the magnetic field lines. The satellite also had a camera to image the Northern Lights in ultraviolet light.
The launch with Ariane was successful and Viking ended up in an orbit at an altitude of just over 800 km, but to reach the desired peak altitude, Viking was equipped with a large solid-fuel rocket motor that was fired over the southern hemisphere. The research instruments on Viking worked excellently, but the radiation at the high altitude negatively affected all electronics and finally, after 444 days in space, in May 1987, the satellite's battery could no longer be charged and the Viking mission was over. Approximately 250 scientific reports and articles with results from Viking have been published. Viking will stay in space for about 100,000 years.
During Viking, the researchers gathered for so-called campaigns (two-week periods) at the ground station at Esrange. During a typical satellite passage, they sat in front of their terminals, all in the same room, and looked at the data in real time while on a monitor they could see the images from the camera on board the Viking showing the Northern Lights. This very direct contact with each other and with the satellite was a very unusual way of conducting space research for the space industry at the time. This is what Sven Grahn wrote in his diary for October 6, 1986:
”… Went up the mountain ["Radar mountain" at Esrange] in the evening. There was a meeting with the Viking researchers who showed each other nice color slides of some day old spectrograms from Viking ..."