The mission, formally called Stardust-NeXT, for New EXploration of Tempel-1, was launched on its way in 2006. On Monday night it came within 181 kilometers (112 miles) miles of the comet, taking pictures and measuring the amount and composition of dust in the comet's coma, the plume of gas that surrounds it. It approached the comet at about 10.6 kilometers (6.7 miles) per second, making it one of the fastest probes that has yet flown.
Stardust made its closest approach at 11:39 p.m. Eastern and after that, swung around its high-gain antenna towards Earth to transmit its data. The comet and spacecraft are about 336 million kilometers (209 million miles) away, so signals take a full 18 minutes to get to Earth."
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