一年後：新視野號探測器在冥王星上的十大發現（雙語）

Where were you at 7:49 a.m. Eastern Time on July 14, 2015?

東部時間2015年7月14日早上7點49分，你在哪裡？

Three billion miles from Earth, NASA』s New Horizons spacecraft, moving at speeds that would get it from New York to Los Angeles in about four minutes, was pointing cameras, spectrometers, and other sensors at Pluto and its moons – distant worlds that humankind had never seen up close – recording hundreds of pictures and other data that would forever change our view of the outer solar system.

在地球三十億英里外，NASA新視野號探測器正以從紐約至洛杉磯約四分鐘的速度移動著，它正在將攝像機、光譜儀和其它感測器對準冥王星以及其衛星—那是一個人類從未近距離窺探過的遙遠世界—它們記錄下的上百張圖片和其它數據，將從此改變我們對外太陽系的認知。

「New Horizons not only completed the era of first reconnaissance of the planets, the mission has intrigued and inspired. Who knew that Pluto would have a heart?」 said NASA』s Director of Planetary Science Jim Green. 「Even today, New Horizons captures our imagination, rekindles our curiosity, and reminds us of what』s possible.」

「新視野號不僅代表了第一個行星探勘時代的結束， 這次任務還激起了更大範圍的興趣和靈感。誰能想到冥王星表面會有一顆愛心呢？」NASA的行星科學總指揮Jim Green如是說。「即使是今天，新視野號捕捉了我們的想像力、重燃了我們的好奇心、並提醒了我們可能性的存在。」

NASA"s New Horizons spacecraft captured this high-resolution enhanced color view of Pluto"s moon Charon just before closest approach on July 14, 2015. Charon』s striking reddish north polar region is informally named Mordor Macula. Credits: NASA/JHUAPL/SwRI

就在2015年7月14日NASA新視野號探測器最近距離飛掠冥王星前不久，它捕捉到了冥衛一卡戎的高解析度增強彩色圖像。卡戎顯眼的微紅北極地區已被非正式命名為「魔多暗斑」（Mordor Macula）。

圖片來源：NASA/JHUAPL/SwRI

To say that New Horizons shook the foundation of planetary science is an understatement—discoveries already culled from the pictures and compositional and space environment readings have not only introduced us to the Pluto system, but hint at what awaits as scientists examine other worlds in the Kuiper Belt. New Horizons Principal Investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, lists the mission』s most surprising and amazing findings from Pluto (so far):

如果說，新視野號動搖了行星科學的根基仍是保守的說法—從圖像和空間環境成分讀數中篩選出的發現，不僅將我們引入冥王星系統，並且為科學家們調查柯伊伯帶的其它世界暗示了可能的發現。新地平線號的首席研究員，來自美國科羅拉多州博爾德西南研究院的Alan Stern列出了此次任務中，關於冥王星（至今為止）最令人驚嘆的發現：

The complexity of Pluto and its satellites is far beyond what we expected.

冥王星及其衛星的複雜程度遠超預期。

The degree of current activity on Pluto』s surface and the youth of some surfaces on Pluto are simply astounding.

當前冥王星的地表活躍度，和部分表層的年輕程度簡直令人震驚。

Pluto』s atmospheric hazes and lower-than-predicted atmospheric escape rate upended all of the pre-flyby models.

冥王星的大氣灰霾，與低於預期的大氣逃逸比率，顛覆了所有的預飛掠模型。

Charon』s enormous equatorial extensional tectonic belt hints at the freezing of a former water ice ocean inside Charon in the distant past. Other evidence found by New Horizons indicates Pluto could well have an internal water-ice ocean today.

卡戎的巨大赤道伸展構造帶在遙遠的過去，卡戎內部曾經存在水冰洋，如今已經凍結。新視野號發現的其他證據表明，如今的冥王星很可能蘊含有一個內部水冰洋。

All of Pluto』s moons that can be age-dated by surface craters have the same, ancient age—adding weight to the theory that they were formed together in a single collision between Pluto and another planet in the Kuiper Belt long ago.

冥王星的衛星中，所有能通過其表面隕石坑來測定年代的均有同樣古老的年齡——這進一步證明了一個理論，即這些衛星均形成於很久以前冥王星和柯伊伯帶中某顆行星的一次碰撞中。

Charon』s dark, red polar cap is unprecedented in the solar system and may be the result of atmospheric gases that escaped Pluto and then accreted on Charon』s surface.

卡戎的暗紅色極冠在太陽系是前所未有的現象，而它極有可能是大氣氣體從冥王星逃逸後吸積在卡戎表面的結果。

Pluto』s vast 1,000-kilometer-wide heart-shaped nitrogen glacier (informally called Sputnik Planum) that New Horizons discovered is the largest known glacier in the solar system.

新視野號發現冥王星上存在一千公里寬的心形固氮冰川（非正式地稱之為史潑尼克平原），那是目前太陽系中已知的最大冰川。

Pluto shows evidence of vast changes in atmospheric pressure and, possibly, past presence of running or standing liquid volatiles on its surface – something only seen elsewhere on Earth, Mars and Saturn』s moon Titan in our solar system.

有證據顯示出冥王星大氣壓的巨大變化，甚至在其表面可能曾存在過流動或靜止的液體揮發物—這種現象之於太陽系，只在地球、火星和土衛六泰坦上發生過。

The lack of additional Pluto satellites beyond what was discovered before New Horizons was unexpected.

除了之前新視野號發現的衛星外，冥王星別無衛星，這一事實出乎意料。

Pluto』s atmosphere is blue. Who knew?

冥王星大氣是藍色的。誰能想到呢？

「It』s strange to think that only a year ago, we still had no real idea of what the Pluto system was like,」 said Hal Weaver, New Horizons project scientist from the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. 「But it didn』t take long for us to realize Pluto was something special, and like nothing we ever could have expected. We』ve been astounded by the beauty and complexity of Pluto and its moons and we』re excited about the discoveries still to come.」

「難以置信的是，僅僅一年前，我們對於冥王星系統是怎樣的情況仍是毫無所知。」Hal Weaver說道，他是來自馬里蘭州勞雷爾約翰霍普金斯大學應用物理實驗室的新視野號項目科學家。「但是沒花多久，我們就意識到冥王星的特殊性，特殊到我們前所未料。我們被冥王星及其衛星的美麗與複雜所震撼，更讓人激動的是，各類發現還在接踵而來。」

New Horizons is now nearly 300 million miles beyond Pluto, speeding to its next destination deeper into the Kuiper Belt, following NASA approval of an extended mission. About 80 percent of the data stored on the spacecraft』s recorders has been sent to Earth; transmission of the remainder will be complete by October.

新地平線號目前在冥王星大約三億英里之外，獲得NASA擴展任務的批准後，它正加速前往深入柯伊伯帶的下一個目的地。探測器記錄中所存儲的數據，80%已經被傳送回地球；剩餘的傳輸將於10月前完成。

Illustration of Pluto and its next science target, 2014 MU69, with the trajectory of New Horizons in yellow.

Credits: Alex Parker

該圖像為冥王星和關於它的下一個科學目標，2014MU69，黃色部分為新地平線號軌跡。

圖片來源：Alex Parker