The constant increase in the amount of space debris poses a serious threat for active satellites and the International Space Station (ISS) because the debris remains in orbit at an altitude of 700 kilometres for decades up to centuries.
DLR researchers at the Institute of Technical Physics are working on a laser-based tracking method to determine the precise location of orbiting objects. Based on the position data, it is possible to calculate precise orbits of space debris that in turn enable efficient avoidance manoeuvres.
In order to determine the orbit of the objects, they are tracked by an optical telescope and at the same time deliberately irradiated with laser pulses. The distance to the object is calculated using the time that the laser light needs to travel from the ground to the piece of debris and back again. With this combination of laser propagation time measurement and position determination of objects in space, DLR researchers can determine the trajectory of an object at an altitude of 1000 kilometres to within a few metres.
In the long term, methods for the removal of space debris must be developed. To achieve this, objects could be slowed down by the evaporation of surface material using targeted laser irradiation, so that they enter a lower orbit and then burn up in the atmosphere. At the Institute of Technical Physics, concepts for the development of laser systems and tracking methods as well as operating security considerations are being devised.