On 20 February 2008, the U.S. uses an SM-3 missile to shoot down a non-functioning satellite. The main reason the U.S. acted was to ensure that the frozen hydrazine onboard the wayward satellite was destroyed before it could hit the Earth.
Without intervention, the satellite would have fallen to Earth on its own in early March 2008. The fuel tank, full of 1,000 pounds of hydrazine, could have survived re-entry and dispersed harmful or even potentially deadly fumes over an area the size of two football fields.
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