In almost 50 years of space activities, more than 4800 launches have placed some 6000 satellites into orbit, of which only a minor fraction - about 800 - are still operational today. Only 6 percent of the catalogued orbit population are operational spacecraft, while 38 percent can be attributed to decommissioned satellites, spent upper stages and mission-related objects (launch adaptors, lens covers, etc.).
The remaining 56 percent originates from more than 200 in-orbit fragmentations which have been recorded since 1961. Except for a few collisions (less than 10 accidental and intentional events), the majority of the 200 break-ups were explosions of spacecraft and upper stages.
Note: Images in this gallery are artist's impressions; size of debris objects are exaggerated as compared to the Earth.
The launch of the first artificial satellite by the Soviet Union in 1957 marked the beginning of the utilization of space for science and commercial activity. During the Cold War, space was a prime area of competition between the USSR and USA, reaching its climax with the race to the Moon in the 1960s. In 1964 the first TV satellite was launched into a geostationary orbit in order to transmit the Olympic games from Tokyo. Later, Russian launch activities declined while other nations set up their own space programs. Thus, the number of objects in Earth orbit has increased steadily - by two hundred per year on average.
Note: The debris field shown in the image is an artist's impression based on actual data. However, the debris objects are shown at an exaggerated size to make them visible at the scale shown.
