Viking (V3, V4L)
Viking was Sweden’s first research satellite. It was built and equipped primarily to investigate and understand auroral processes, such as how the particles that give rise to the aurora are accelerated and how they interact with different electric and magnetic fields. It also investigated the structure and dynamics of the aurora as well as electromagnetic radiation.
Viking was launched on 22 February 1986 with an Ariane rocket from Kourou in French Guiana along with the French remote sensing satellite SPOT.
Scientists from IRF were responsible for two of the scientific instruments on board, V4L, a wave and plasma density instrument, and V3, a hot plasma / energetic particle experiment.
The V4L instrument functioned for Viking’s lifetime (February 1986 – May 1987) and delivered time series of wave electric fields, plasma density variations and background plasma density of various phenomena, mostly related to the aurora region. IRF in Uppsala had the main responsibility for V4L.
The particle instrument V3 had several spectrometers built into seven sensor units, and could thus determine the distribution and energy levels of the charged particles. The Principal Investigator and responsible for V3 was Rickard Lundin at IRF in Kiruna.
Research groups from Canada, Denmark, France, Norway, the USA and Germany, among others, had the main responsibility for other instruments or participated in the data analysis.
Successful project
Viking proved to be a very successful project and unique data was collected for more than a year, which was slightly longer than planned. The project was led by the Swedish Space Corporation (SSC) on behalf of the Swedish National Space Board (now the Swedish National Space Agency). The satellite was developed by Saab Space (now included in RUAG Space) with Boeing Aerospace as a subcontractor.
Esrange was the ground station for Viking, and researchers from many countries gathered there to process data in close to real time. At that time it was a significant novelty to be able to control the research instruments directly in cooperation with the operators who sending commands to the satellite.
The Viking satellite is relatively small with a weight of 286 kilograms and will to orbit around the Earth for a long time, but without delivering any more data. The original orbit was over the Poles, with a minimum altitude of more than 800 km and a maximum altitude of more than 13,500 km.