Technologies to mitigate space debris and improve in-orbit satellite services

Sustainability in space and the fight against the accumulation of waste produced in Earth orbit are the objectives pursued by PERSEI Space, a company whose partners include two researchers from Universidad Carlos III de Madrid (UC3M) and which has developed a space electrodynamic tether technology that is useful in this area.

This spin-off, which has been incubated by the European Space Agency (ESA) and is being supported by the Center for Innovation in Entrepreneurship and Artificial Intelligence (C3N-IA) of the UC3M—Leganés Tecnológico Science Park, has the support of the European Innovation Council through the E.T.PACK-F and E.T.COMPACT projects.

"Our company was created to address two of the biggest challenges facing the space sector today: space debris removal and in-orbit services. The latter allow us to extend the useful life of satellites and carry out key activities such as refueling, repair and towing of satellites from their initial orbit to their final destination," explains Jesús Manuel Muñoz Tejeda, CEO and co-founder of PERSEI Space.

Space debris poses a very serious threat to the sustainability of space operations since, due to the high speed at which debris moves in Earth orbit, an impact can result in severe damage and the generation of more small debris. In addition, the current density of space debris is already above the threshold that triggers an uncontrolled chain of collisions, known as the Kessler syndrome.

To get rid of this space junk, PERSEI Space is working on space tethers, a technology with three key features. "The first is that it does not need fuel, unlike other de-orbiting systems. The second is that our technology is reversible; it can serve to both increase and decrease the orbital height. And the third feature is that it is scalable, since it serves a wide range of satellite masses. With all this, we can develop autonomous de-orbiting systems, a unique feature of our technology that ensures that the satellite does not leave space debris, even if it ceases to be operational," explains Manuel Muñoz Tejeda.

Space tethers

The system is based on electrodynamic tethers, aluminum ribbons, generally hundreds of meters long and a few centimeters wide, which work by interacting with the ionospheric plasma and Earth's magnetic field to generate a force known as the Lorentz force.

"The interaction of the electric current in the tether with Earth's magnetic field generates a drag force capable of lowering the satellite's altitude, facilitating its de-orbiting without requiring fuel, which translates into significant savings in mass and volume," says Gonzalo Sánchez Arriaga, professor in the UC3M Department of Aerospace Engineering and co-founder of PERSEI Space.

PERSEI Space is leading a first demonstration mission for 2026, thanks to a launch opportunity facilitated by ESA's Flight Tickets Initiative and the European Commission. The deorbiting equipment for this demonstration has a mass of 20 kg, and includes a space tether approximately 430 meters long that, once in orbit, will deploy and interact with the ambient plasma and magnetic field, generating a drag force that will deorbit the satellite within a few months. The development of the technology could not be more timely, as new European and US guidelines have reduced the maximum time satellites can remain in orbit after the end of their mission from 25 to 5 years.

Provided by Carlos III University of Madrid