Laser radiation for cleaning space debris from lower earth orbits

High-power laser radiation may be the most feasible means to mitigate the threat of collisions of a space station or other valuable space assets with orbital debris in the size range of 1-10 cm. The utilization of a laser in orbit is investigated. Use of the laser allows both the direct protection against an impact and the removal of all debris passing at some distance. Under laser irradiation, part of the debris material is ablated and provides an impulse to the debris fragment. Proper direction of the impulse vector either deflects the object trajectory (defense option) or forces the debris on a trajectory through the upper atmosphere, where it burns up (cleaning option). The limitations of the laser method for both options are illustrated by sample calculations for an averaged pulsed laser power of 100 kW and debris consisting of either aluminum or carbon. Under favorable geometrical conditions, debris masses of 100 g at a passing distance of up to 70 km can be removed, and debris on a collision flight path can be deflected by 500 m and more. An orbital debris removal system should be established and operated by an international society.