http://goo.gl/pJJ7oG 冥王星有多大？新视野号总结长达几十年的争论 NASA’s New Horizons mission has answered one of the most basic questions about Pluto—its size. NASA的新视野号任务已能回答关於冥王星最基本的问题之一：它的大小。 Mission scientists have found Pluto to be 1,473 miles (2,370 kilometers) in diameter, somewhat larger than many prior estimates. Images acquired with the Long Range Reconnaissance Imager (LORRI) were used to make this determination. This result confirms what was already suspected: Pluto is larger than all other known solar system objects beyond the orbit of Neptune. 此任务科学家们发现冥王星是1473英里（2370公里），直径比许多现有的估计更大些。 远距离侦察成像仪（LORRI）获得的图像已被用来进行这个确认。这一结果证实了以往的 猜测：冥王星比海王星以外的轨道所有其他已知的太阳系天体较大。 注：不过阋神星(Eris)不是估计比冥王星大些吗(直径约2400 KM)？2006年冥王星被降成 矮行星，Eris的发现占了其中一个原因。 “The size of Pluto has been debated since its discovery in 1930. We are excited to finally lay this question to rest,” said mission scientist Bill McKinnon, Washington University, St. Louis. 「冥王星的大小自1930年发现後已争论不停，我们很高兴终於让这个问题能停止。」 任务科学家 Bill McKinnon 表示 (华盛顿大学圣路易斯)。 Pluto’s newly estimated size means that its density is slightly lower than previously thought, and the fraction of ice in its interior is slightly higher. Also, the lowest layer of Pluto’s atmosphere, called the troposphere, is shallower than previously believed. 冥王星新估算的大小意味着它的密度比以前认为的略低、与冰在其内部的比例略高。另外 ，冥王星的大气，称为对流层的最底层，比以前认为的还浅。 Measuring Pluto’s size has been a decades-long challenge due to complicating factors from its atmosphere. Its largest moon Charon lacks a substantial atmosphere, and its diameter was easier to determine using ground-based telescopes. New Horizons observations of Charon confirm previous estimates of 751 miles (1208 km) kilometers) across 测量冥王星的大小一直是一个长达数十年的挑战，因为它的大气复杂的因素。其最大的 卫星凯伦缺乏实质的大气层，它的直径是更容易使用地面望远镜来确认。新视野号观察 凯伦确认直径为751英里（1208公里）超过以前的估计。 ※凯伦(Charon)是罗马神话的地狱渡船夫，给钱才给渡河。(可参考圣斗士冥界篇) LORRI has also zoomed in on two of Pluto’s smaller moons, Nix and Hydra. 远距离侦察成像仪（LORRI）也放大了两个冥王星较小的卫星，尼克斯和许德拉。 ※尼克斯(Nix)，是希腊神话中代表黑夜的女神。 许德拉(Hydra)，希腊罗马神话中是守卫地狱的九头蛇。 尼克斯(Nix)与许德拉(Hydra)，相信是取自新视野号(New Horizons)字母开头的N与H “We knew from the time we designed our flyby that we would only be able to study the small moons in detail for just a few days before closest approach,” said New Horizons Principal Investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado. “Now, deep inside Pluto’s sphere of influence, that time has come.” 「最初规划飞越任务时就已经知道，我们只有在最靠近冥王星前後的短短几天的时间内 能仔细研究它的小卫星。」 西南研究所，科罗拉多州博尔德市的新地平线首席研究员Alan Stern表示。 「现在，深入冥王星影响的范围内，研究其小卫星的时刻已到。」 ※注：这段原本翻得很烂，感谢juotung大提供更优的翻译！ Nix and Hydra were discovered using the Hubble Space Telescope in 2005. Even to Hubble, they appeared as points of light, and that’s how they looked to New Horizons until the final week of its approach to Pluto. Now, the latest LORRI images show the two diminutive satellites not as pinpoints, but as moons seen well enough to measure their sizes. Nix is estimated to be about 20 miles (about 35 kilometers) across, while Hydra is roughly 30 miles (roughly 45 kilometers) across. These sizes lead mission scientists to conclude that their surfaces are quite bright, possibly due to the presence of ice. 尼克斯和许德拉是用哈伯太空望远镜在2005年发现，甚至到哈伯发现时，他们只是一个 光点，他们与新视野号对望，直到靠近冥王星的最後一周。现在，最新的LORRI图像显示 两个身材矮小的卫星没有精确定位，但卫星能见度足够来量测它们的大小。尼克斯估计 大约20英里（约35公里）以上，而许拉德是大约30英里（约45公里）以上。这些尺寸导致 任务科学家得出结论，它们的表面很光亮，可能是由於冰的存在。 What about Pluto’s two smallest moons, Kerberos and Styx? Smaller and fainter than Nix and Hydra, they are harder to measure. Mission scientists should be able to determine their sizes with observations New Horizons will make during the flyby and will transmit to Earth at a later date. 那麽冥王星的另外两个最小的卫星，塞伯拉斯和冥河呢？体积更小，比尼克斯和许拉德 微弱，他们是难以测量的。任务科学家应该较能确定与观察是新视野号於飞越期间来看 它们的大小和稍後几天将讯息传送回到地球。 注：塞伯拉斯(另翻「科伯罗司」（Kerberos）)，即地狱三头犬(可参考圣斗士冥界篇)。 冥河(Styx)，字义上就是冥界之河，希腊神话里面有五条冥河，Styx是誓约之河 神话中对着誓河发誓是非常神圣庄严的一件事，一旦违背就会遭到严厉的惩罚 另外，与其说是冥王星有五颗卫星，倒不如说是四颗卫星绕行冥王星和凯伦 双星系统 --

※ 发信站: 批踢踢实业坊(ptt.cc), 来自: 114.42.62.6 ※ 文章网址: https://webptt.com/cn.aspx?n=bbs/sky/M.1436890577.A.F7C.html 1推 hoyunxian: 其实希腊神话里面有五条冥河，Styx是誓约之河 07/15 09:45 了解，我把这字义加上去了，感恩！ 好像是，WIKI也有记录，那我也注明一下好了，谢谢 多谢，那一段我翻得很怪，马上修改^^ 推 SWW: 这个系统实在太酷了~~~ 07/16 00:43 感谢提醒，我现在就去改正，3Q ※ 编辑: Js1233 (114.42.60.162), 07/17/2015 21:19:00