Space debris is one of the biggest challenges to the safe operation of satellites and future rocket launches, which it can damage. The number of debris in space is constantly growing – estimates show that there are more than 36,000 objects larger than 10 centimeters and more than 130 million pieces smaller than 1 centimeter. Different methods for removing debris are therefore being researched around the world – from contact-based systems to non-contact approaches. Contact solutions are considered particularly complex because the fragments move unpredictably and the systems can easily be damaged if accessed directly.
Researchers rely on a contactless approach
In the EU ALBATOR project, in addition to the Christian Albrechts University of Kiel (CAU), four other partners – the Justus Liebig University of Gießen, the 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 the transmission of momentum through a plasma jet of high-energy particles. The beam is not intended to “blast” the space debris, but rather to specifically change its path and movement. As a rule, the objects tumble, which means they rotate uncontrollably. With the help of the ion beam, this rotation must first be stopped before the object can be captured and towed away, for example with a gripping arm or net. Alternatively, the entire maneuver can be carried out contactlessly by pushing the object solely with the ion beam. The aim is to either cause the scrap to re-enter the Earth’s atmosphere in a controlled manner so that it burns up, or to transfer it to a so-called “graveyard orbit”.
