This artist rendition released by NASA shows an explosion, top left, on the Tempel 1 comet after the probe from the Deep Impact spacecraft collided with the comet early Monday, July 4, 2005. The successful strike 133.6 million km away from Earth marked the first time a spacecraft touched the surface of a comet.

　　人类斗胆撞彗星

　　By Alicia Chang

　　They weren't a red, white and blue spectacle, but the cosmic fireworks NASA created by blasting a hole in a comet were something for scientists to cheer about this Fourth of July weekend.

　　The brighter-than-expected white flash of light climaxed a daring mission "that's something to be proud of on America's birthday," said Rick Grammier, the mission's project manager at NASA's Jet Propulsion Laboratory.

　　Dramatic,sci-fi-like images

　　犹如科幻电影般精彩

　　About 12 hours after the barrel-sized Deep Impact space probe smashed into a comet half the size of Manhattan, scientists showed off dramatic, sci-fi-like images. Photos shot by the impactor probe as it awaited its suicidal collision revealed for the first time the surface of the comet Tempel 1 as it closed in at 23,000 mph.

　　The close-ups revealed not so much the pickle-shaped comet that scientists originally thought, but one that looked more like a potato, lumpy and pocked. Michael A'Hearn, an astronomer at the University of Maryland and Deep Impact principal investigator, likened it to a muffin or loaf of bread.

　　The impact released a bright flash followed by a larger one as a plume of trapped gas and debris spewed from the comet's belly into space, backlit by the sun. The cloud blocked scientists' view of the excavated crater and it could be weeks before the dust disappears. Still, scientists were confident they accomplished their mission because they were able to see the crater's shadow in the photos.

　　"Our experiment went very, very well," said co-investigator Pete Schultz of Brown University, who seemed to be brimming with enthusiasm. "We touched a comet and we touched it hard."

　　Origins of the sun and planets

　　expected to de revealed

　　科学家期待揭示太阳行星诞生秘密

　　The mission seemed to spark enthusiasm of skywatchers too. Officials at JPL said the Deep Impact web site had 1 billion hits, compared to some 400 million hits for the Mars mission.

　　Scientists said the comet appears to have a soft, dusty surface with crater-like features. Trapped ice seems to be below the surface, possibly containing the primordial ingredients of the solar system, Schultz said. Scientists are hoping to get to the core of this rocky, ice-filled structure to learn about the origins of the sun and planets.

　　A giant cloud of gas and dust collapsed to create Earth's solar system about 4.5 billion years ago, and comets formed from the leftover building blocks of the solar system.

　　The mission also gives scientists some information about how they might one day stop a comet if one threatens Earth — but they would need a far larger strike to make a significant dent in turning a comet off-course, A'Hearn said.

　　Last image taken three seconds defore impact

　　探测器最后影像在撞击前3秒发出

　　Launched on its mission Jan. 12 from Cape Canaveral, Fla., the Deep Impact spacecraft traveled 268 million miles to get the comet in its sights. Late Saturday, it released its copper "impactor" probe and pointed it toward Tempel 1, 83 million miles from Earth. The probe made a 24-hour solo flight toward the comet, heading for a smash-up.

　　The camera of the probe temporarily blacked out twice, probably from being sandblasted by comet debris, NASA scientists said. Still, on battery power and tumbling toward the comet, using thrusters to get a perfect aim, it took pictures right up to the final moments. The last image was taken three seconds before impact.

　　Soon after it crashed on the comet's sunlit side, the mothership came within 310 miles of the comet and took pictures of the receding comet as it flew away. More images will be produced by an arsenal of space observatories in the coming days.

　　The energy produced from the impact was equivalent to exploding five tons of dynamite and it caused the comet to shine six times brighter than normal.

　　The crash was not visible from Earth except through a telescope in western parts of the Western Hemisphere. But the impact late Sunday was cause for celebration, not only to scientists in mission control, but for the more than 10,000 people camped out at Hawaii's Waikiki Beach to watch it on a giant movie screen.

　　Brian Spears, a 19-year-old anthropology student and Star Trek fan from San Bernardino, Calif., called the event "really a key point in our whole lives. We might find out the origins of how we came along."

　　"It's almost like one of those science fiction movies," said Steve Lin, a Honolulu physician.

　　Impact never posed any danger to Darth

　　炮轰慧星对地球没有任何威胁

　　The cosmic crash did not significantly alter the comet's orbit around the sun and NASA said the experiment never posed any danger to Earth — unlike the scary comet in the 1998 movie, "Deep Impact."

　　Scientists at mission control erupted in applause and exchanged hugs as a voice on a speaker proclaimed, "Team, we got a confirmation."

　　It was a milestone for the U.S. space agency, because no other space mission has flown this close to a comet. In 2004, NASA's Stardust craft flew within 147 miles of Comet Wild 2 en route back to Earth carrying interstellar dust samples.

　　In Darmstadt, Germany, controllers at the European Space Agency erupted into applause when the collision occurred. "The Deep Impact mission brought the world together in an excellent opportunity to make a new step into the advancement of cometary science," said the ESA's David Southwood.

　　The European agency was photographing the event with its Rosetta spacecraft, which will attempt to rendezvous with a comet in 2014.

　　"I had some doubts, quite frankly, but it was quite spectacular and a deserved success," said Manfred Warhaut, who heads the Rosetta mission. "The whole thing was so flawlessly put in place and executed it deserves some respect."

　　太平洋时间3日22时52分(北京时间4日13时52分)，美国宇航局“深度撞击”号探测器释放的撞击器“击中”目标——坦普尔1号彗星，地面控制大厅里一片欢呼，“炮轰”彗星大片正式上演。

　　这项史无前例的“炮轰”彗星计划始于1999年11月1日，美宇航局于2005年1月12日成功发射“深度撞击”号探测器。在4日撞击彗星之前，“深度撞击”号走过了4.31亿公里的漫长太空之旅，终于迎来了与坦普尔1号“亲密接触”的激动人心时刻。

　　撞击器击中彗星的彗核后，会在其表面轰出“弹坑”，使其内部物质暴露出来供研究。据预测，撞击会造成彗核表面的冰雪、尘埃等溅起，好比在太空中放出一个大“焰火”。

　　科学家们认为，彗核中含有太阳系初生时遗留的物质，希望借助此次撞击对太阳系诞生的过程有更多了解。美宇航局专家表示，这次撞击不会改变彗星的轨道，也不会对地球构成危险。