Critical number of spacecraft in low Earth orbit: using satellite fragmentation data to evaluate the stability of the orbital debris environment

Previous studies have concluded that fragments from random collisions in low Earth orbit will cause the orbital debris population to increase despite efforts to minimize the accumulation of debris. New data from the orbital history of fragments in space and the laboratory hypervelocity breakup of a payload more accurately confirms this conclusion. The conclusions are reached that the orbital debris environment for much of low Earth orbit is unstable and will seek a higher equilibrium even if no new debris is added to the environment. Some regions may be slightly above a runaway level, where no equilibrium is possible as long as the number of intact objects remains constant. The rate of increase for collision fragments is currently low, but would increase rapidly with increases in the intact population.