Abstract :
There exists a large amount of man-made debris in low Earth orbit. The quantity of this debris is growing every year as a result of on-going activities in space. Much of the debris consists of particles which are too small to be tracked from the ground, but nevertheless pose a threat to spacecraft. This paper examines the possibility of an orbiting radar which, over a period of time, could measure debris positions and velocities and thereby build up a database of debris orbits. Spacecraft could use this database for advance warning of impending collisions and maneuver themselves out of the collision path, thereby mitigating the long-term risk of collision damage.