Wikipedia
Fēngyún , abbreviated FY, are China's weather satellites. China has launched polar orbit and geosynchronous orbit meteorological satellites since 1988. On January 11, 2007 China destroyed one of these satellites (FY-1C) in a test of an anti-satellite missile.
The satellites in the FY-1 series are polar-orbiting sun-synchronous orbits. The satellites in the FY-2 series are in geosynchronous orbit.
Meteorological satellites also important in oceanography, agriculture, forestry, hydrology, aviation, navigation, environmental protection and national defense. They contribute to the national economy and to preventing and mitigating disasters. The latest satellites monitor bad weather around the clock, particularly convective rainstorms, thunderstorms and hailstorms. They also monitor developing sandstorms as well as air quality and provide early warnings.
According to NASA, the intentional destruction of FY-1C created 2,841 high-velocity debris items, a larger amount of dangerous space junk than any other space mission in history.