Newswise — Finland’s first science satellite, Foresail-1, successfully launched into orbit on a SpaceX Falcon-9 rocket on May 25 from Cape Canaveral in Florida, USA. In addition to collecting data about near-Earth radiation, Foresail-1 will test a plasma brake designed to bring small satellites out of orbit, which could help address the growing problem of space junk.

According to the European Space Agency, over 13,000 satellites have been launched into orbit since Sputnik-1 went up in 1957. That number is expected to grow now that miniature satellites are becoming common and more countries are joining the space industry. Most satellites aren’t brought down after their mission ends, littering Earth’s orbit with discarded equipment. This debris poses a risk not only to satellites that are still in use but also to spacecraft travelling beyond Earth’s orbit.

To address this problem, the Foresail-1 satellite, developed by Aalto University, carries a plasma brake device developed by the Finnish Meteorological Institute. Instead of using propellant to slow down, the plasma brake is based on a long steel tether which will be extended from the satellite in a few months. Interactions between the tether and charged particles will slow the satellite, bringing it down from orbit.

‘A new satellite platform was developed to carry out this unique experiment in Low Earth Orbit. The development process took years and involved a lot of testing,’ says Assistant Professor Jaan Praks, the mission leader. Foresail-1 will test the new system and measure the braking force created by the plasma brake.

In addition to bringing a satellite down from orbit, the plasma brake could also be used to manoeuvre a satellite into a different orbit. Commercial development of the technology is already underway, meaning it will be available for use in other satellites following a successful demonstration in space.

Foresail-1 also carries a particle telescope, developed at the University of Turku, to study near-Earth radiation, which poses a hazard to satellites. These measurements will help design satellites that are more resilient to radiation damage.

The satellite was developed by the Finnish Centre of Excellence in Research of Sustainable Space, which includes teams from Aalto, the University of Helsinki, the University of Turku, and the Finnish Meteorological Institute.

‘With long-term funding from the Academy of Finland, we have created Finland's first scientific space programme, which aims to develop more sustainable space exploration,’ says Professor Minna Palmroth of the University of Helsinki, the director of the Centre of Excellence.