旅行者1号到达太阳风之尽头

新年伊始，翻译一篇报道活跃一下版面吧，祝大家在新的一年里，有所开拓，有所收获，生活幸福，健康开心～

原文：NASA Probe Sees Solar Wind Decline

                               
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上图：旅行者号接近星际空间的艺术想象图，版权所有NASA/JPL

December 13, 2010 PASADENA, Calif.
2010年12月13日，美国加利福尼亚州帕萨迪纳

The 33-year odyssey of NASA's Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind.
NASA的探测器旅行者1号历经三十三年的冒险旅程，到达了遥远的太阳系边缘的一个角落——在这里太阳风不再向外吹拂。

Now hurtling toward interstellar space some 17.4 billion kilometers (10.8 billion miles) from the sun, Voyager 1 has crossed into an area where the velocity of the hot ionized gas, or plasma, emanating directly outward from the sun has slowed to zero. Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars.
现在，飞奔在距离太阳174亿公里的星际空间中，旅行者1号已经进入了一个从太阳发出的炽热电离气体（等离子体）的速度减小到零的区域。科学家们怀疑太阳风已经被来自恒星间区域的星际风的压力所影响而转向两侧。

The event is a major milestone in Voyager 1's passage through the heliosheath, the turbulent outer shell of the sun's sphere of influence, and the spacecraft's upcoming departure from our solar system.
这一事件是旅行者1号穿过太阳势力范围的湍动的外壳层——日鞘过程中的重要里程碑，标志着这艘宇宙飞船即将离开我们的太阳系。

Launched on Sept. 5, 1977, Voyager 1 crossed the termination shock in December 2004 into the heliosheath. Scientists have used data from Voyager 1's Low-Energy Charged Particle Instrument to deduce the solar wind's velocity. When the speed of the charged particles hitting the outward face of Voyager 1 matched the spacecraft's speed, researchers knew that the net outward speed of the solar wind was zero. This occurred in June, when Voyager 1 was about 17 billion kilometers (10.6 billion miles) from the sun.
发射于1977年9月5日的旅行者1号在2004年12月跨过激波边界进入了日鞘。科学家们已经通过旅行者1号上面的低能带电粒子仪测量出了太阳风的速度。当打在旅行者1号前端的带电粒子速度等于飞船自身速度时，研究人员意识到此时总的向外的太阳风速已经变成了零。这发生在今年6月，当时旅行者1号距离太阳约170亿公里。

Because the velocities can fluctuate, scientists watched four more monthly readings before they were convinced the solar wind's outward speed actually had slowed to zero. Analysis of the data shows the velocity of the solar wind has steadily slowed at a rate of about 20 kilometers per second each year (45,000 mph each year) since August 2007, when the solar wind was speeding outward at about 60 kilometers per second (130,000 mph). The outward speed has remained at zero since June.
因为速度可能存在起伏，科学家们又继续收集了四个月的数据，以确认太阳风向外的速度真的降为了零。对太阳风速数据的分析显示，从2007年8月以来太阳风速每年持续降低约20千米每秒，而当时太阳风以60千米每秒的速度向外吹拂。自从今年6月以来，太阳风向外的速度一直保持为零。

The results were presented today at the American Geophysical Union meeting in San Francisco.
这一结果被发布在今天的美国地理协会旧金山会议上。

"When I realized that we were getting solid zeroes, I was amazed," said Rob Decker, a Voyager Low-Energy Charged Particle Instrument co-investigator and senior staff scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "Here was Voyager, a spacecraft that has been a workhorse for 33 years, showing us something completely new again."
“当我意识到我们获得了一个可靠的零值，我很吃惊”，约翰霍普金斯大学应用物理实验室（位于美国马里兰州劳瑞尔）的资深科学家、低能带电粒子仪的合作研究员罗伯戴克尔说，“这可是旅行者号，一艘勤勤恳恳工作了三十三年的宇宙飞船，又给我们展示了一些全新的东西。”

Scientists believe Voyager 1 has not crossed the heliosheath into interstellar space. Crossing into interstellar space would mean a sudden drop in the density of hot particles and an increase in the density of cold particles. Scientists are putting the data into their models of the heliosphere's structure and should be able to better estimate when Voyager 1 will reach interstellar space. Researchers currently estimate Voyager 1 will cross that frontier in about four years.
科学家们相信旅行者号并没有跨过日鞘进入星际空间。进入星际空间意味着热粒子的密度会突然降低而冷粒子的密度将升高。科学家们把数据放入他们的日鞘结构模型，应该可以更好的估计出什么时候旅行者号将到达星际空间。目前研究人员估计旅行者号将在大约四年后到达这一边界。

"In science, there is nothing like a reality check to shake things up, and Voyager 1 provided that with hard facts," said Tom Krimigis, principal investigator on the Low-Energy Charged Particle Instrument, who is based at the Applied Physics Laboratory and the Academy of Athens, Greece. "Once again, we face the predicament of redoing our models."
“在科学中，没有什么能像实际测量一样动摇原有的观念，旅行者1号用可靠的事实证明了这一点”，低能带电粒子仪的负责人、任职于应用物理实验室和希腊雅典学院的汤姆克里明吉斯说，“又一次，我们不得不面对重做我们模型的窘境。”

A sister spacecraft, Voyager 2, was launched in Aug. 20, 1977 and has reached a position 14.2 billion kilometers (8.8 billion miles) from the sun. Both spacecraft have been traveling along different trajectories and at different speeds. Voyager 1 is traveling faster, at a speed of about 17 kilometers per second (38,000 mph), compared to Voyager 2's velocity of 15 kilometers per second (35,000 mph). In the next few years, scientists expect Voyager 2 to encounter the same kind of phenomenon as Voyager 1.
旅行者1号的姐妹探测器——旅行者2号发射于1977年8月20号，已经到达距离太阳142亿公里远的地方。这两艘宇宙飞船以不同的速度沿着不同的轨迹前进，旅行者1号的速度是17千米每秒，比15千米每秒的旅行者2号跑得更快一些。科学家们预计，在接下来的几年里，旅行者2号将会遇到旅行者1号类似的情景。

The Voyagers were built by NASA's Jet Propulsion Laboratory in Pasadena, Calif., which continues to operate both spacecraft. For more information about the Voyager spacecraft, visit: http://www.nasa.gov/voyager . JPL is a division of the California Institute of Technology in Pasadena.
旅行者号是由美国宇航局（NASA）喷气动力实验室（位于加利福尼亚州帕萨迪纳）建造并操作维护的，如需要更多关于旅行者号的信息，请访问http://www.nasa.gov/voyager。喷气动力试验室（JPL）是帕萨迪纳加州理工大学的一个部门。

一路好走吧——————

(⊙v⊙)嗯，旅行者带着人类的希望继续前行吧！！！

一路走好，不送

太牛了！我在想他现在就靠那么点太阳能还能工作多长时间

传说中的威者

向着位置而勇猛前进！

谢谢楼主分享，翻译的很流畅！

谢谢分享，看了这篇文章想起了一部纪录片《旅行到宇宙边缘》，是部蛮不错的天文学纪录片。
推荐星友们观看。

勇者无畏。

核动力的~就是牛啊！

宇宙太大，太阳系太小！

走出太阳系，太伟大啊。

核动力的驱动就是耐用微型的用三十几年都还没用完，如果以后真发明了热核发电，到时真的是太强悍

不知道出了太阳系还能联系上不