Space debrisMaking space safer by spotting, removing space debris

Published 2 July 2015

Scientists estimate that there are now some 20,000 particles of space junk measuring more than ten centimeters in diameter hurtling around Earth at an average velocity of 25,000 kilometers per hour, not counting the 700,000 or so particles with a diameter of between one and ten centimeters. Although small, these items of space debris are traveling so fast that they could easily damage or destroy an operational satellite. A new German space surveillance system, scheduled to go into operation in 2018, will help to prevent such incidents.

Space debris poses a growing threat to satellites and other spacecraft, which could be damaged in the event of a collision. A new German space surveillance system, scheduled to go into operation in 2018, will help to prevent such incidents. The tracking radar is being developed by Fraunhofer researchers on behalf of DLR Space Administration.

Traffic congestion is also an issue in space where, in addition to the dense network of satellites, orbiting space debris is increasingly transforming the paths on which they travel into a junkyard populated with burnt-out rocket stages and fragments of disintegrated spacecraft.

Farunhofer reports that scientists estimate that there are now some 20,000 particles of space junk measuring more than ten centimeters in diameter hurtling around Earth at an average velocity of 25,000 kilometers per hour, not counting the 700,000 or so particles with a diameter of between one and ten centimeters. Although small, these items of space debris are traveling so fast that they could easily damage or destroy an operational satellite. The situation is exacerbated by the fact that space debris has a tendency to multiply exponentially through a kind of snowball effect. Whenever two particles collide, they break up into a greater number of smaller particles. Unless preventive measures are taken, the rapid multiplication of space debris could soon put an end to spaceflight as we know it.

There is urgent need for action. The Space Administration division of the German Aerospace Center (DLR) has been tasked by the German government with designing the German space program. In turn, DLR Space Administration has awarded a contract to the Fraunhofer Institute for High Frequency Physics and Radar Techniques (FHR) in Wachtberg to develop and build a radar system for monitoring and tracking objects in low-Earth orbit. This is the region of space in which the risk of collisions is at its greatest — especially at an altitude of 800 kilometers above Earth. The German Federal Ministry for Economic Affairs and Energy (BMWi) has granted a total of €25 million to finance the GESTRA (German Experimental Space Surveillance and Tracking Radar) project over a four-year period.