An international consortium is developing an ion-beam method for the safe removal of debris from Earth orbit. The ion beam is intended to halt uncontrolled object motion and enable their relocation. Kiel University is receiving €639,000 in funding for this work as part of the EU project ALBATOR.
Space debris is one of the greatest challenges to the safe operation of satellites and future rocket launches, as these can be damaged by debris. The number of fragments in space is growing steadily – estimates indicate that there are more than 36,000 objects larger than 10 centimeters and more than 130 million pieces smaller than 1 centimeter. Worldwide, a range of debris removal methods are therefore being explored – from contact-based systems to non-contact approaches. Contact solutions are considered particularly complex, as fragments move unpredictably and the systems can be easily damaged during direct capture.
Researchers rely on a non-contact approach
Within the EU project ALBATOR, alongside Kiel University’s CAU, four additional partners – Justus Liebig University Giessen, Universidad Carlos III de Madrid (Spain), and the companies NorthStar Earth & Space (Luxembourg) and OsmosX (France) – are pursuing a non-contact approach: the so-called ion-beam shepherd method.
The method is based on momentum transfer via a plasma beam composed of high-energy particles. The beam is not intended to “destroy” the debris, but to specifically alter its trajectory and rotational motion. As a rule, the objects are tumbling, meaning they are rotating uncontrollably. Using the ion beam, this rotation must first be stopped before the object can be captured and towed away, for example using a robotic arm or net. Alternatively, the entire maneuver can be carried out without contact by pushing the object solely with the ion beam. The aim is either to guide the debris into controlled re-entry into Earth’s atmosphere so that it burns up, or to move it into a so-called “graveyard orbit.”
Beam intended to transfer thrust to debris
Within the ALBATOR project, the researchers are developing a novel plasma-beam system that can be precisely directed at space debris. In addition to building and optimizing the system, models are being created to simulate plasma discharge and beam-surface interactions. The goal is to transfer thrust to debris fragments as efficiently as possible.
The CAU team contributes its expertise in beam–surface interactions. Using a patented force probe developed in Kiel, the researchers measure how strongly ion beams act on different materials – such as solar panels, gold-coated Kapton foils, or protective coatings. Detailed computer simulations provide complementary data that help to better understand the complex processes involved. Both approaches feed into a materials database that is essential for accurately targeting the ion beam at space debris and influencing its motion.
Dr. Thomas Trottenberg, project leader at CAU from the Plasmatechnology research group, emphasizes: “If we are to use space safely in the long term, we must avoid space debris or actively remove it. That is precisely where we are making our contribution.”
The ALBATOR project (ecr-bAsed muLticharged ion Beam for Active debris removal and oTher remediatiOn stRategies) is being funded for 42 months under the HORIZON–EIC Pathfinder Challenge program with a total of around four million euros. Of this amount, approximately €639,000 is allocated to CAU. Through the European Innovation Council (EIC) Pathfinder, the EU supports visionary, high-risk projects at an early stage of development that have the potential to create radically new technologies and markets.
