Since the launch of Sputnik on 4 October 1957, more than 4,200 launches have placed some 5500 satellites into orbit. Currently about 700 satellites are used operationally for science and other applications. Space debris comprise the ever-increasing amount of inactive space hardware in orbit around the Earth as well as fragments of spacecraft that have broken up, exploded or otherwise become abandoned.
It is crucial to start right away with implementation of the mitigation measures. We have simulated the future GEO environment in case no measures are taken. This is the "business-as-usual" scenario. In the top panel a much cleaner space environment can be observed if the number of explosions is reduced drastically and if no mission-related objects are ejected. However, to stop the ever increasing amount of debris more ambitious mitigation measures need to be taken. In the long run, spacecraft and rocket stages have to be returned to Earth after completion of their mission.
In order to illustrate the Sun and Moon perturbations the fragments from the first debris cloud are shown in white.
