I am in search of another planet in the universe where life exists.
我正在宇宙中寻找另一颗有生命的行星。
I can't see this planet with my naked eyes or even with the most powerful telescopes we currently possess.
靠肉眼肯定看不到，即使借助如今最强大的望远镜也看不到。
But I know that it's there. And understanding contradictions that occur in nature will help us find it.
但我坚信它的存在。了解自然界的矛盾法则，能帮助我们找到它。
On our planet, where there's water, there's life.
在我们地球上，哪里有水，哪里就有生命。
So we look for planets that orbit at just the right distance from their stars.
因此我们将目光锁定在那些与恒星的距离正合适的行星。
At this distance, shown in blue on this diagram for stars of different temperatures,
这一距离，在这张示意图中以蓝色表示，根据恒星温度的高低而不同，
planets could be warm enough for water to flow on their surfaces as lakes and oceans where life might reside.
能保证行星足够温暖，使水保持液态，形成湖泊和海洋，就有可能孕育生命。
Some astronomers focus their time and energy on finding planets at these distances from their stars.
一些天文学家将时间和精力投入到搜寻那些与其所围绕恒星的距离在这一范围内的行星。
What I do picks up where their job ends.
而我的工作紧随其后。
I model the possible climates of exoplanets. And here's why that's important:
我建立这些系外行星的气候模型。这项工作很重要：
there are many factors besides distance from its star that control whether a planet can support life.
因为要决定行星上是否有生命存在，除了与恒星的距离外，还有许多其他因素。
Take the planet Venus. It's named after the Roman goddess of love and beauty,
以金星为例。它以罗马爱和美之女神的名字命名，
because of its benign, ethereal appearance in the sky.
因为它看起来如此优雅而美丽。
But spacecraft measurements revealed a different story.
然而宇宙飞船测量的结果完全不是这么回事。
The surface temperature is close to 900 degrees Fahrenheit, 500 Celsius.
金星表面的温度接近900华氏度，也就是500摄氏度。
That's hot enough to melt lead. Its thick atmosphere, not its distance from the sun, is the reason.
这温度足以融化铅。原因并不在于它与太阳的距离，而在于它厚厚的大气层。
It causes a greenhouse effect on steroids, trapping heat from the sun and scorching the planet's surface.
金星的大气层引发的温室效应，将来自太阳的热量牢牢锁住，将金星地表变成一片焦土。
The reality totally contradicted initial perceptions of this planet.
这与我们之前对金星的想象完全不一样。
From these lessons from our own solar system,
我们太阳系的这个例子告诉我们，
we've learned that a planet's atmosphere is crucial to its climate and potential to host life.
行星的大气层对于其气候特点和能否孕育生命至关重要。
We don't know what the atmospheres of these planets are like
我们无法了解那些（可能孕育生命的）行星的大气情况，
because the planets are so small and dim compared to their stars and so far away from us.
因为跟它们围绕的恒星相比，它们又小又暗，而且离我们非常遥远。
For example, one of the closest planets that could support surface water -- it's called Gliese 667 Cc
比如，离我们最近的，可能有液态水存在的行星之一，叫做“格利泽667Cc”
such a glamorous name, right, nice phone number for a name -- it's 23 light years away.
多美的名字啊，对吧，做电话号码应该不错--离我们23光年。
So that's more than 100 trillion miles.
也就是超过100万亿英里。

Trying to measure the atmospheric composition of an exoplanet passing in front of its host star is hard.
想要在一颗系外行星从它的主恒星前经过时，测量它的大气成分太难了。
It's like trying to see a fruit fly passing in front of a car's headlight.
就好比要看清一只从车头灯前飞过的果蝇一样。
OK, now imagine that car is 100 trillion miles away, and you want to know the precise color of that fly.
而且，这辆车还远在100万亿英里之外，你还想看清这只果蝇的颜色。
So I use computer models to calculate the kind of atmosphere a planet would need to have a suitable climate for water and life.
因此我用计算机建模，来计算一颗行星要形成适宜水和生命存在的气候，需要何种大气类型。
Here's an artist's concept of the planet Kepler-62f, with the Earth for reference.
这是一张“开普勒62f”行星的概念图，旁边是用来做对比的地球。
It's 1,200 light years away, and just 40 percent larger than Earth.
它距离我们1200光年，体积只比地球大40%。
Our NSF-funded work found that it could be warm enough
我们的研究--由国家科学基金会资助--发现它温度适宜，
for open water from many types of atmospheres and orientations of its orbit.
可能存在液态水，它的大气拥有多种成分，还有它的公转轨道。
So I'd like future telescopes to follow up on this planet to look for signs of life.
因此我希望未来的望远镜能继续观测这颗行星，寻找生命存在的迹象。
Ice on a planet's surface is also important for climate.
行星表面的冰层对于气候同样重要。
Ice absorbs longer, redder wavelengths of light, and reflects shorter, bluer light.
冰能吸收波长较长、更靠近红端的光，反射波长较短、更靠近蓝端的光。
That's why the iceberg in this photo looks so blue.
这就是为什么这张照片里的冰山看起来这么蓝。
The redder light from the sun is absorbed on its way through the ice.
阳光里偏红的光在穿过冰层时被吸收。
Only the blue light makes it all the way to the bottom.
只有蓝色的光一路走到底。
Then it gets reflected back to up to our eyes and we see blue ice.
然后反射到我们的眼睛里，我们就看到了蓝色的冰。
My models show that planets orbiting cooler stars could actually be warmer than planets orbiting hotter stars.
我的模型显示，恒星温度越低，其行星反而更温暖，恒星温度越高，其行星反而更寒冷。
There's another contradiction -- that ice absorbs the longer wavelength light from cooler stars,
这又是一个矛盾之处--冰层吸收来自温度较低恒星发出的波长较长的光，
and that light, that energy, heats the ice. Using climate models to explore how these contradictions
而这些光，这些能量，又加热了冰层。运用气候模型来研究这些矛盾，
can affect planetary climate is vital to the search for life elsewhere.
看它们如何影响行星的气候，对于寻找地外生命至关重要。
And it's no surprise that this is my specialty.
而我命中注定要从事这个行业。
I'm an African-American female astronomer and a classically trained actor
我是一名非裔美籍女天文学家，也是受过古典艺术训练的演员，
who loves to wear makeup and read fashion magazines,
我喜欢化妆，喜欢时尚杂志，
so I am uniquely positioned to appreciate contradictions in nature --
所以上帝派我来理解这些矛盾--
and how they can inform our search for the next planet where life exists.
并利用它们来寻找下一个有生命的行星。
My organization, Rising Stargirls, teaches astronomy to middle-school girls of color, using theater, writing and visual art.
我成立的“新星女孩”组织，通过戏剧、写作和视觉艺术的方式，向非白人女中学生传授天文学知识。
That's another contradiction -- science and art don't often go together,
这也是一对矛盾--科技和艺术看起来不同路，
but interweaving them can help these girls bring their whole selves to what they learn,
但两者的交融可以帮助这些姑娘们实现自我，学有所成，
and maybe one day join the ranks of astronomers who are full of contradictions,
也许有一天她们也能成为那些充满矛盾的天文学家中的一员，
and use their backgrounds to discover, once and for all, that we are truly not alone in the universe. Thank you.
运用自身所学，彻底证明我们在茫茫宇宙中并不孤独。谢谢大家。