探测冥王星的探测器（新视野号探测器在冥王星上的十大发现）

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

东部时间2015年7月14日早上7点49分，你在哪里？

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.

在地球三十亿英里外，NASA新视野号探测器正以从纽约至洛杉矶约四分钟的速度移动着，它正在将摄像机、光谱仪和其它传感器对准冥王星以及其卫星—那是一个人类从未近距离窥探过的遥远世界—它们记录下的上百张图片和其它数据，将从此改变我们对外太阳系的认知。

“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.”

“新视野号不仅代表了第一个行星探勘时代的结束， 这次任务还激起了更大范围的兴趣和灵感。谁能想到冥王星表面会有一颗爱心呢？”NASA的行星科学总指挥Jim Green如是说。“即使是今天，新视野号捕捉了我们的想象力、重燃了我们的好奇心、并提醒了我们可能性的存在。”

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新视野号探测器最近距离飞掠冥王星前不久，它捕捉到了冥卫一卡戎的高分辨率增强彩色图像。卡戎显眼的微红北极地区已被非正式命名为“魔多暗斑”（Mordor Macula）。

图片来源：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):

如果说，新视野号动摇了行星科学的根基仍是保守的说法—从图像和空间环境成分读数中筛选出的发现，不仅将我们引入冥王星系统，并且为科学家们调查柯伊伯带的其它世界暗示了可能的发现。新地平线号的首席研究员，来自美国科罗拉多州博尔德西南研究院的Alan Stern列出了此次任务中，关于冥王星（至今为止）最令人惊叹的发现：

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

冥王星及其卫星的复杂程度远超预期。

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

当前冥王星的地表活跃度，和部分表层的年轻程度简直令人震惊。

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

冥王星的大气灰霾，与低于预期的大气逃逸比率，颠覆了所有的预飞掠模型。

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构造带在遥远的过去，卡戎内部曾经存在水冰洋，如今已经冻结。新视野号发现的其他证据表明，如今的冥王星很可能蕴含有一个内部水冰洋。

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.

冥王星的卫星中，所有能通过其表面陨石坑来测定年代的均有同样古老的年龄——这进一步证明了一个理论，即这些卫星均形成于很久以前冥王星和柯伊伯带中某颗行星的一次碰撞中。

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.

卡戎的暗红色极冠在太阳系是前所未有的现象，而它极有可能是大气气体从冥王星逃逸后吸积在卡戎表面的结果。

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.

新视野号发现冥王星上存在一千公里宽的心形固氮冰川（非正式地称之为史泼尼克平原），那是目前太阳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.

有证据显示出冥王星大气压的巨大变化，甚至在其表面可能曾存在过流动或静止的液体挥发物—这种现象之于太阳系，只在地球、火星和土卫六泰坦上发生过。

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

除了之前新视野号发现的卫星外，冥王星别无卫星，这一事实出乎意料。

Pluto’s atmosphere is blue. Who knew?

冥王星大气是蓝色的。谁能想到呢？

“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.”

“难以置信的是，仅仅一年前，我们对于冥王星系统是怎样的情况仍是毫无所知。”Hal Weaver说道，他是来自马里兰州劳雷尔约翰霍普金斯大学应用物理实验室的新视野号项目科学家。“但是没花多久，我们就意识到冥王星的特殊性，特殊到我们前所未料。我们被冥王星及其卫星的美丽与复杂所震撼，更让人激动的是，各类发现还在接踵而来。”

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.

新地平线号目前在冥王星大约三亿英里之外，获得NASA扩展任务的批准后，它正加速前往深入柯伊伯带的下一个目的地。探测器记录中所存储的数据，80%已经被传送回地球；剩余的传输将于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

该图像为冥王星和关于它的下一个科学目标，2014MU69，黄色部分为新地平线号轨迹。

图片来源：Alex Parker

“Our entire team is proud to have accomplished the first exploration of Pluto and the Kuiper Belt—something many of us had worked to achieve since the 1990s,” said Stern. “The data that New Horizons sent back about Pluto and its system of moons has revolutionized planetary science and inspired people of all ages across the world about space exploration. It’s been a real privilege to be able to do that, for which I’ll be forever indebted to our team and our nation.”

“整个团队为完成了冥王星和柯伊伯带的首次探测感到自豪—这是我们自九十年代起所致力于达成的目标，”Stern说，“由新地平线号传送回来的冥王星及其卫星数据已经使行星科学彻底变革，世界各个年龄段的人们吸引到太空探索中。能够参与到这项工作中，真是非常荣幸，为此我将永远感激我的团队和国家。”（翻译：钱丹辰 校核： sherry）

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