A secret Soviet-navy satellite called Cosmos 954, which was launched on September 18, 1977, was powered by a compact nuclear reactor, making its failure, breakup, and re-entry particularly frightening.
Two events in recent years have greatly increased the amount of debris on orbit. On February 10, 2009, the active Iridium 33 satellite collided with the defunct Cosmos 2251 satellite, and created about 2,000 tracked objects. On January 11, 2007, the Chinese deliberately destroyed the FY-1C satellite in a test of an anti-satellite weapon, creating more than 3,000 tracked objects. The tracked objects represent a small fraction of the debris objects created.