Fig. 7

Spatial object density for low Earth orbits for objects 5 cm and larger. The plot was created using ESA’s MASTER-2009 software (v7.2). The spatial object density peak just below 800 km is created by the fragments from the two debris clouds of the Iridium 33 and Cosmos 2251 spacecraft which collided in early 2009. The peak just above that altitude is the debris from the Chinese anti-satellite test in which the meteorology satellite Fengyun 1C was deliberately destroyed by a ground-to-space missile (Liou and Johnson 2009; Johnson et al. 2007)