20条近期新闻

On Sunday, several hundred engineers and scientists will gather at the Jet Propulsion Laboratory in Pasadena, Calif., and await the end of the Galileo spacecraft in a suicide plunge into Jupiter''s dense atmosphere. 周日，数百名工程师和科学家,将聚集在加利福尼亚州的帕沙德纳的喷气推进实验室，静候伽利略号航天飞机自杀性插入木星周围稠密大气层的结局。 They are the kind of professionals who try to resist anthropomorphizing their machines, even one like Galileo, which has been a longtime companion in their lives and careers. But they freely concede that they will be there at the end as an act of homage. 这些专家尽力阻止使机器人性化，即便是相处很久的伽利略号。但他们不得不勉强的承认他们会满怀敬意的守到最后时刻。 "It will be the equivalent of a wake," said Dr. Claudia Alexander, manager of the project. “它将是一个有意义的轨迹”，这个项目负责人Claudia Alexander博士评论道。 Few flight teams have had to contend with a spacecraft more demanding of their attention and ingenuity. 很少飞行队要求航空飞船有更多的注意力和灵活性。 Launched in 1989 after a long delay caused by the loss of the space shuttle Challenger in 1986, Galileo took six years going to Jupiter, almost half a billion miles away, by a circuitous route dictated by the limited power of its initial rocket boost. 由于1986挑战者号航空飞船的坠毁，推迟了很久的伽利略号终于于1989年发射。它花了6年的时间到达木星，几乎走了5亿英里距离。 From then on, the three-ton spacecraft was tormented by as many afflictions as poor Job. 从那时起，3吨重的航空飞船被认为是一项要多痛苦有多痛苦的乏味工作 The main antenna, the one that scientists counted on for the return of pictures and data of Jupiter and its four largest moons, failed to unfurl. Engineers had to rely on a smaller antenna and an improvised system of data shorthand. 科学家们所指望的用于返回木星和他的四个最大的卫星的图片和数据的主要天线没能正常打开，因此他们不得不依靠一个小型天线和一个临时准备的数据速记系统。 Galileo was further hobbled by an erratic tape recorder. After the craft began orbiting Jupiter in 1995, repeated zappings from the planet''s intense radiation belts damaged other instruments. 伽利略号又被一个漂浮在太空的磁带录音机所拖累。在飞船1995年后围绕木星轨道运动时，从行星的强辐射带发射的循坏的跳过节目的辐射损坏了其他一些仪器。 In nearly all cases, engineers managed to reprogram software to overcome or work around the setbacks. As recently as last November, in its last encounter with a Jovian moon, tiny Amalthea, the spacecraft "got hammered again by radiation," Dr. Alexander said. 在所有的情况中，工程师们试图重新编写软件以克服遇到的挫折。去年十一月份，在它的最后一次与木星的卫星木卫五相遇时， “飞船又被辐射给破坏了,” Alexander博士说。 The spacecraft''s fault-detection system came to the rescue once again, turning off nearly all operations and saving the science data from the encounter. 飞船的错误监察系统再次起了作用：它几乎关闭了所有操作并将相遇的全部科学数据记录了下来。 But the tape recorder was left stuck. Flight controllers applied electrical current to the recorder, on and off and on again, repeatedly, until the molecular structure was altered enough to unstick the recorder for transmitting data. 但是磁带记录机却粘着了。飞行控制器应用了电流将记录机反复地打开关上，直至分子结构改变才使磁带与记录机分开。 "Miracles continued to happen on this mission," Dr. Alexander said. “奇迹再度发生，”Claudia Alexander博士说。 Indeed, in spite of everything, scientists rate Galileo as one of the most successful missions of planetary exploration. Galileo''s eight-year orbit of Jupiter included several close encounters of each of Jupiter''s major satellites, Ganymede, Callisto, Io and Europa. No two were found to be anything alike. 确实，尽管发生了种种事故，科学家认为伽利略号是行星探索任务中最成功的一次。在伽利略号围绕着木星的八年的轨道上，它与木星的几颗主要的卫星有过好几次近距离接触，比如Ganymede, Callisto, Io and Europa。它们中没有任何两个是相同的。 Ganymede is not only the largest moon in the solar system, but it is also larger than Mercury and Pluto. Galileo discovered that Ganymede had a strong magnetic field, "something no one thought a moon would have," said Dr. Rosaly Lopes-Gautier, a member of the project''s science team. Ganymede在太阳系中不是最大的卫星，但他要比Mercury 和冥王星大多了。伽利略号发现Ganymede还有强磁场。“这是从来没有任何人都想到卫星会有磁场，”小组的一个项目负责人Rosaly Lopes-Gautier博士说。 Icy Callisto appears to be the most heavily cratered object in the solar system. Io is bubbling with erupting volcanoes, 152 by Dr. Lopes-Gautier''s latest count. The phenomenon was discovered on previous flybys by Voyager spacecraft, but Galileo determined how plentiful and persistent the eruptions are. The lava flows are hotter than anything seen on Earth in two billion years. 冰冻的木卫四看上去像是太阳系中表面坑洞最多的一个星体。Io的火山正在爆发。据Rosaly Lopes-Gautier 博士最近的统计，至少有152个。这个现象早先就被经过的航行者号发现过，但伽利略号却更详细地展示了这些爆发是多么的壮观和持久。四处流淌的熔浆比地球在近二十亿年间的任何东西都要热。 Europa has given scientists the most reason to celebrate and speculate. In Galileo''s eight flybys, the appearance of Europa''s frozen crust suggested that it covered an immense ocean. And where there is so much liquid water, could there also be some forms of life? 木卫二是科学家们最值得庆祝和思索的。在伽利略号八次靠近中，它的冰冻的外壳暗示了它下面覆盖的广大的海洋。这么多的液态水的地方，会不会也有某些形式的生命存在呢？ That discovery sealed Galileo''s ultimate fate. If the spacecraft, after running out of maneuvering fuel, should crash into Europa, it might contaminate that moon with stowaway microbes from Earth and confound future searchers for indigenous life. So the decision was made to vaporize the spacecraft by putting it on a collision course with Jupiter. 这个发现决定了伽利略的最终命运。如果它用完燃料后坠落在木卫二上，它可能会因从地球携带的微生物污染这个星球，并会混淆以后关于这个卫星上的本土生命的研究。因此，一致决定将伽利略号的航道调整，使其与木星相撞而坠毁。 "The course is unalterable," Dr. Alexander said. "The last fuel was expended several months ago, to make sure we hit the planet." “它的命运是无法改变的，”亚历山大博士说，“最后的燃料数月前已经被扔掉以保证它将在木星上坠毁。” Tracking data show that the craft, traveling 30 miles a second toward the end, will crash into Jupiter on its night side. At 12:50 p.m., Pacific time, the old Galileo hands in Pasadena, hearing no radio signal, will know that their spacecraft is no more. 飞船的轨道数据显示了它以每秒3 0英里的速度撞入木星的黑面。在太平洋时间凌晨0:50分，岁月苍苍的伽利略号将失去讯号。此时，它已经坠毁了。