Japan’s experiment to clean up space junk earlier this year may have ended in failure, but the world’s space agencies haven’t given up on the problem yet. The European Space Agency (ESA) recently proposed using a magnetic space tug to sweep up some of the debris that has accumulated in space. The magnetic tug is designed to corral derelict and broken satellites, putting a dent in the space junk problem.
Could magnetic forces be the key to cleaning up space trash? Scientists at the Institut Supérieur de l’Aéronautique et de l’Espace at France’s University of Toulouse hope to find out. They’re exploring magnetic attraction or repulsion as part of their investigation into the most effective way to keep satellites in formation out in space.
Researcher Emilien Fabacher explained it this way: “With a satellite you want to deorbit, it’s much better if you can stay at a safe distance, without needing to come into direct contact and risking damage to both chaser and target satellites. So the idea I’m investigating is to apply magnetic forces either to attract or repel the target satellite, to shift its orbit or deorbit it entirely.”
Many satellites are already equipped with what are called magnetorquers, or electromagnets that can use the magnetic field of the Earth to change the satellite’s orientation. So a magnetic space tug could simply target those magnetorquers. The chaser satellite would need a strong magnetic field, but that could be generated with superconducting wires cooled to cryogenic temperatures, according to ESA.
The chaser satellite could even catch multiple derelict satellites and position them in formation. Over 100 million pieces of space trash now orbit Earth, and 29,000 of them are large enough to cause damage. Fabacher is working on the project as part of his PhD research, which is supported by ESA’s Networking/Partnering initiative.