欧“智能1号”飞船成功撞月
[ 2006-09-04 14:26 ]
Europe's first spacecraft to the moon ended its three-year mission Sunday by crashing into the lunar surface in a volcanic plain called the Lake of Excellence, to a round of applause in the mission control room in Germany. Hitting at 2 kilometers per second, the impact of the SMART-1 spacecraft was expected to leave a 3-meter-by-10-meter crater and send dust kilometers above the surface. Observatories watched the event from Earth and scientists hoped the cloud of dust and debris would provide clues to the geological composition of the site. "That's it -- we are in the Lake of Excellence," said spacecraft operations chief Octavio Camino as applause broke out in mission control in Darmstadt, Germany. "We have landed." Minutes later, officials showed off a picture captured by an observatory in Hawaii displaying a bright flash from the impact. Launched into Earth's orbit by an Ariane-5 booster rocket from Kourou, French Guiana, in September 2003, SMART-1 used its ion engine to slowly raise its orbit over 14 months until the moon's gravity grabbed it. The engine, which uses electricity from the craft's solar panels to produce a stream of charged particles called ions, generates only small amounts of thrust but only needed 80 kilograms of xenon fuel. The craft's X-ray and infrared spectrometers have gathered information about the moon's geology that scientists hope will advance their knowledge about how the moon's surface evolved and test theories about how the moon came into being. The spacecraft has also been taking high-resolution pictures of the surface with a miniaturized camera. (Agencies)
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