Assessment of the consequences of the Fengyun-1C breakup in low Earth orbit

On 11 January 2007, the People’s Republic of China conducted a successful anti-satellite test against one of their defunct polar-orbiting weather satellites. The target satellite, called Fengyun-1C, had a mass of 880 kg and was orbiting at an altitude of about 863 km when the collision occurred. Struck by a direct-ascent interceptor at a speed of 9.36 km/s, the satellite disintegrated, spreading the cataloged fragments between 200 and 4000 km, with the highest concentration near the breakup height. By the end of April 2008, 2377 pieces of debris, including the original payload remnant, had officially been cataloged by the US Space Surveillance Network. Of these, nearly 1% had reentered the Earth’s atmosphere. This deliberate act is the largest debris-generating event on record, and its consequences will adversely affect circumterrestrial space for many years.In an attempt to assess the impact of the Fengyun-1C breakup on the low Earth environment, the cloud of cataloged debris was propagated for nearly 8 years, taking into account the relevant orbit perturbations and a debris cloud ballistic coefficient distribution based on orbit decay calibrations. The immediate consequence of the Chinese anti-satellite test was to significantly increase the probability of collision with man-made debris. For the Italian spacecraft launched in the first half of 2007, the collision probability with cataloged objects increased by 10% for AGILE, in equatorial orbit, and by 60% for COSMO-SkyMed 1 and 2, in sun-synchronous orbit. During the next few years, the debris cloud generated by the Fengyun-1C breakup was found to remain relatively stable, with nearly 80% of the cataloged fragments still in orbit about 9 years after the event.