Unless you've spent quality time on the International Space Station, this is probably not a view you are super familiar with.
除非你在国际空间站待过些时日，这个景色可能对你很陌生。
This is the east coast of the United States.
这是美国的东海岸。
That's New York down there in the lower right, and it's a band of light all the way up through Washington DC.
右下角就是纽约，那条光带直通华盛顿哥伦比亚特区。
Those cities are shining like jewels, highways are traced by webs of light.
这些城市像珠宝闪耀，网状的光路点缀着高速公路。
And all of that light is super photogenic. But there's a problem.
这些光看上去十分上镜。但是有一个问题。
That light is meant to be illuminating our sidewalks, and our streets and our houses.
这些光本该照亮我们的人行道、我们的街道和房屋。
Instead, it's actually going up into the sky and out into the universe, where it's not doing any of us any good.
但是与此同时，这些光也照亮了天空，发射到宇宙中，而这对我们毫无利处。
When I see photos of this, of the Earth, I see environmental catastrophe. Those aren't jewels, those are tumors.
当我看到地球的这张图片时，我看到的是一场环境灾难。这些不是珠宝，而是毒瘤。
I'm an astronomer, so it's really no surprise probably to anyone that I've always loved the night sky. I'm kind of a walking cliché.
我是一名天文学家，我迷恋夜空，这也应该不足为奇。我自己有点像行走的陈词滥调。
But when I was growing up in Minnesota, one of my favorite things to do on a summer evening
但是当我在明尼苏达州长大时，在夏夜我最喜欢做的事
was grab my old Raggedy Ann sleeping bag and take it out into a field behind my house, where I would spend hours looking at the night sky.
就是拿上我旧旧的布安妮睡袋到我家后面的田野里，整宿地观望夜空。
And to do this, I had to brave not only the darkness,
为此，我不仅要征服黑暗，
but also swarms of mosquitoes, and my sleeping bag really didn't smell very good.
还要忍受蜂拥而至的蚊虫，而且我睡袋的气味也不怎么好闻。
But there was one particular star that I would look for, night after night.
但是有那么一颗特别的星星，我每夜都在寻找。
And then I would play this game where I would try to focus on that star so intensely,
然后我会自己玩这样的一个游戏：我会紧盯着那颗星星，
that everything else would fade from my view and that single star would be all that I could see.
直到其它的一切都都从我的视野里渐渐淡去，而那颗星星是我唯一可以看到的东西。
I could only ever hold on to that focus for a few fleeting moments.
像那样集中注意力，我只能维持几个瞬间。
But when I did, I felt this deep sense of connection to the universe.
但每当我这么做时，我感受到了自己和宇宙之间的深刻连接。
And almost a sense of vertigo, like I was going to fall into space.
一股眩晕感袭来，我感觉自己仿佛掉入了太空中。
And when this happened -- I know this sounds kind of ridiculous,
当这种感觉出现时--我知道这听上去很可笑，
but I would simultaneously feel unfathomably insignificant and also kind of weirdly important.
但是我同时也感到这种深不可测的渺小，又莫名的重要。
That star I looked to night after night was called Vega.
那颗我夜夜观望的星星叫织女星。
Vega is the brightest star in the constellation Lyra, which is not coincidentally the name of one of my dogs.
织女星是天琴座中最明亮的恒星，并非巧合，这也是我狗狗的名字。
But this experience is being lost. My favorite constellation, Lyra, this is what it would look like from Manhattan.
但是这个体验正在逐渐消失。我最喜欢的星座，天琴座，在曼哈顿的夜空中看上去是这样的。
For people who live in urban and suburban environments, if they go outside at night and look up,
对于住在城市和郊区中的人们，如果他们仰望夜空，
instead of being awestruck by the majesty of the universe, they see pretty much nothing.
他们无法对宇宙的雄伟心生敬畏，因为他们在空中几乎什么也看不见。
These unremarkable, completely blank night skies, of course are due to all of the light we produce at night.
这些不起眼的、看似空旷的夜空，当然都是因为我们在夜晚产生的灯光。
Those very same lights we see all the way from space are shining up into the atmosphere,
正是那些我们从太空中看到的光直射到大气层中，
where they bounce around and create this featureless smog of light.
到处反射，形成光雾。
And that featureless smog of light has a name. It's called light pollution.
这平淡无奇的光雾有一个名字。它叫光污染。
As an astronomer, I can actually tell how bad light pollution is by the brightness of stars I can see in the sky.
作为一名天文学家，我可以通过恒星的亮度判断光污染的严重性。
And it turns out that when you're trying to unlock the secrets of the cosmos,
事实证明，如果你想解开宇宙之谜，
it's really helpful to be able to see the cosmos. And... Truth.
首先得能看到宇宙才行。而且...是真的。
And this light that we're trying to detect is coming from millions or billions of light-years away, and so it's generally pretty faint.
而且这些我们想要探测到的光是从几百万或数十亿光年外来的，所以通常都比较暗淡。
And as an astronomer, I fight with this every day to do my job, and I have to tell you, it is a really big problem.
作为一名天文学家，为了正常工作，我每天都与光污染作斗争，而且我必须告诉你们，这是一个很严重的问题。
But the problem is far worse than just losing some whimsical ability to gaze at the stars.
这个问题的严重性远远超过了失去观赏星空的异想天开的能力。
For example, countless plant and animal species are affected.
比方说，无数的动植物也受到了影响。
So we could talk about sea turtles or pollinators or any of these super important species that are also cute.
我们可以说说海龟，或传粉昆虫，或任何这些非常重要的，同时也很可爱的物种。
Instead, I want to talk about these quietly unassuming dog whelks.
但是，我想要讲的是这些不起眼的犬峨螺。
You may have seen them around and not given them really a whole lot of thought. But they're pretty cool.
你们可能见过它们，却并没有多加留意。但是它们其实挺特别。
So in an entire year a dog whelk will rarely move more than about 10 meters.
在一整年中，一只犬峨螺移动很少超过十米。
That means that when they are attacking their prey they can hit this brisk pace of about a millimeter an hour.
这意味着当它们攻击猎物时，它们会以每小时一毫米的速度冲刺。
And... This works out OK, because they attack things like barnacles.
而且...这其实还凑合，因为它们攻击的是藤壶。
So these dog whelks live in the intertidal area of coasts, where, it turns out, they're a pretty key part of the ecosystem.
这些犬峨螺生活在海岸区的潮间带，在这里，它们是生态系统中关键的组成部分。
Not only are they one of the most dominant invertebrate predators,
它们不仅是重要的无脊柱动物的捕食者，
but other animals, like crabs and birds, think they're pretty tasty.
对于螃蟹和鸟类来说，它们也很可口。
So that leaves these poor snails in a kind of precarious situation,
所以对这些可怜的螺来说，它们处于岌岌可危之地，
because if they go too low in the water, then crabs are a threat,
因为如果它们到浅水区，就会受到螃蟹的威胁，
but if they come out of the water too far, birds are going to have a feast.
但是如果进到深水区，就会成为鸟类的美餐。
Why is an astronomer telling you about dog whelks? I ask that myself.
一名天文学家为什么要和你们讲犬峨螺？我也在自问。
Because their behavior is impacted by light pollution.
因为它们的行为会受到光污染的影响。
For example, if dog whelks are subjected to artificial light at night
举例来说，如果犬峨螺在夜晚遭受人造光源的影响，
they're about twice as likely to stay under the water with a predator.
它们可能有成倍的几率会和捕食者一同待在水下。
And that puts them at increased risk. And it's not like they can make a speedy escape.
这会把它们置于更大的险地，而它们又无法迅速脱身。
And so these... And the other issue is because they literally move at a snail's pace.
所以这些...另一个问题是它们移动得真的慢如蜗牛。
If a population is wiped out, it can take decades to replenish.
如果一个种群被消灭，需要数十年才能慢慢恢复。
And that, in turn, affects the rest of their ecosystem and the other species, like the birds and the barnacles and the crabs.
而这又会影响它们其余的生态系统和其它的物种，比如鸟类、藤壶和螃蟹。
So this is just one small and slimy example of how light pollution can unleash a cascade effect on an entire ecosystem.
这只是一个又小又黏的例子，来展示光污染是如何对整个生态系统产生级联效应的。
Virtually every species that has been studied to date is impacted by light pollution.
几乎每一个至今被研究过的物种都受到了光污染的影响。
And that includes humans. So let's talk about us.
其中也包括人类。接下来讲讲我们自己。

You are probably not surprised to hear that light pollution can affect your ability to sleep well at night.
你们可能已经听说过光污染会影响我们夜间的睡眠质量。
But you might be surprised to hear that light pollution is linked to obesity.
但是你们可能会惊讶于光污染和肥胖症的关联。
In fact, in a recent study they found that light pollution contributed to over 70 percent of the obesity rates in 80 countries.
事实上，最近的研究发现，光污染在80个国家中促成了超过70%的肥胖率。
More than that, light pollution actually contributed about the same amount to excess weight as eating junk food.
不仅如此，光污染对肥胖的贡献度等同于吃垃圾食品。
And it gets worse. For people who are subjected to significant amounts of artificial light at night
而且更糟的是，对于经常在夜晚受到大量人工光源影响的人们来说，
they're about 50 percent more likely to get breast cancer.
他们患上乳腺癌的几率要高50%。
And in fact, light pollution is correlated with types of cancer across the board.
其实，光污染和各种癌症都息息相关。
And in controlled lab experiments there's a direct link between increased artificial light at night and a rate of tumor growth.
在受控制的实验室环境中，夜间人工光源的增加和肿瘤的生长速度有直接关系。
You might be wondering how normal light could possibly impact cancer rates.
你们可能在想，正常的光线怎么可能影响癌症发病率。
It likely all comes down to the super important hormone called melatonin,
这要归结到一个超级重要的荷尔蒙：褪黑素，
which we have evolved over millions of years to produce on a day-night cycle, or a circadian rhythm.
经过通过几百万年的进化，人体已经产生了一个昼夜周期，也称昼夜节律。
What happens is that when light impacts the retina at the back of our eye at night it can disrupt melatonin production,
其中的原理是，当光线在夜间渗透到我们眼后的视网膜时，这会打乱褪黑素的生成，
and when melatonin production is disrupted,
而当褪黑素的生成被打乱时，
a whole chain of other chemical processes are affected, and that includes estrogen production.
一系列其它的化学过程也会接连受到影响，其中就包括雌激素生成。
And when we throw this chemical balance out of whack, really bad things can happen.
当这样的化学平衡被打破时，很糟糕的事情就会发生。
In fact, things are so bad, that the International Agency for Cancer Research has said that
事情的严重性在于，国际癌症研究机提出，
disrupting the human circadian rhythm is a probable carcinogen.
打乱昼夜节律非常可能致癌。
Also, for fun, I want to let you know that light pollution has been linked to,
除此之外，我也想要让各位了解，光污染还是许多其它疾病的起因，
let's see -- headaches, anxiety, depression, diabetes, cardiovascular disease and the list goes on.
比如头疼、焦虑症、抑郁症、糖尿病以及心血管病等许多其它疾病。
But maybe you don't care about your health. We're all going to die anyway, you might as well die in a brightly lit room.
但是或许你不在意自己的健康。反正每个人都会离开，不如在一个灯火通明的地方离开。
The fact that you're laughing about death is kind of amazing.
你们拥有嘲笑死亡的能力还蛮令人惊讶的。
You might still care about money. The money that's spent on that wasted light,
你们可能仍旧会在意钱。这些花费在浪费了的光源上的钱，
and I mean just the light that's going out into the universe, and not doing us any good, is three billion dollars a year.
我只是指射向宇宙的光，对我们无用的光，一年就耗费30亿美元。
That's enough money to build, like, 1,000 utility-grade windmills, or fund the entire DC public-school system for over two years,
这些钱足够建造，例如1000台公用供电级风车，或资助整个华盛顿特区的公校足足两年，
or -- this is my favorite, because I really want one but I can't afford one -- buy 30,000 Tesla Model X SUVs.
或者--这是我最喜欢的，因为我特别想要，但是买不起--3万台特斯拉X型越野车。
And that includes the electric car tax credit. And then there are the existential costs.
而且还包括电动汽车税收抵免。以及存在成本。
I don't have any data on how losing touch with our place in the cosmos impacts us.
我没有具体数据证明若我们不再在意我们在宇宙中的地位，会对我们有怎样的影响。
But I believe that this probably impacts our humanity more than any of the other scary statistics I can share with you.
但是我相信这对人类的影响远超过任何我能和各位分享的骇人数据。
And it's getting worse with time. The amount of light pollution is doubling roughly every 35 years.
而且随着时间推移，这个问题会越来越糟。光污染程度每35年就会翻倍。
That means that within the next decade virtually the entire eastern half of the United States will be perpetually brighter than twilight.
这意味着在接下来的10年中，几乎整个美国的东半部会永久的比黄昏更明亮。
And there's another issue with light pollution. The problem is way worse than we can see with our own eyes.
光污染还带来了另一个问题。这问题比我们能看到的更加严重。
Our eyes have evolved to just detect this tiny range of the full spectrum of light.
人类的肉眼只能看到整个光谱中很小范围的光。
All of this other light that we can't see, this invisible light, also has a pollution problem.
其它我们看不见的光，这些不可见光，也有污染问题。
Mostly it's from modern technology, things like cell phones or car-to-car radar,
大多来自现代科技，比如手机，电子狗，
or now apparently we need appliances that can talk to each other.
还有现在我们必需的通信设备。
All of this modern technology is putting out strong signals
所有这些现代技术发出的强烈信号
that can completely swamp this exceedingly faint light we're trying to detect from the rest of the universe outside Earth,
可以完全淹没我们试图从地球之外的宇宙中探测到的极度微弱的光，
which just for the record, is most of the universe.
也就是来自绝大部分宇宙的光。
And then, there are satellites. Satellites are a problem at both visible and invisible wavelengths.
接着，还有卫星。卫星在可见光和不可见光的波长范围中都是一个问题。
A host of private companies have plans to deploy tens of thousands of satellites into Earth orbit,
许多私人企业都计划在地球轨道上配置几万颗卫星，
where they will not only outnumber, literally outnumber the visible stars in the sky,
这个数量不仅会远超天空中可见的恒星，
while also beaming invisible light back to Earth.
同时也会将不可见光波送回地球。
So for astronomers like me, who use invisible light to study the universe,
所以对于我们这些利用不可见光去研究宇宙的天文学家，
it's going to be like staring at the Sun and trying to see a birthday candle behind it.
就如同凝视烈日，还要尝试在其身后寻找一束烛光。
Alright, I want to be clear that there's nothing inherently wrong with any of this modern technology.
我想强调，这些现代科技本身没有什么问题。
With cell phones or satellites or car radar. I'm not sure about kitchen appliances.
比如手机，卫星和电子狗。至于厨房电器，我不是很清楚。
I haven't broken down and gotten an oven that talks to my cell phone yet.
我还不至于需要一个能和我手机交流的烤箱。
And I use lights at night like everybody else. But here's the thing.
而且，我和大家一样也在晚上用灯。但是有一点。
Some problems in the world, like we've heard about today and you'll hear more about, are overwhelming and they seem intractable.
我们面临的有些问题，比如我们今天讲到的，还有将来你们还会听到的，往往十分棘手，让我们不知所措。
Visible light pollution is not one of these problems. This is actually stupidly simple, OK?
然而可见光污染并不属于这种问题。它其实极其的简单。
So here are five super simple things you can do.
有五件很简单的事，是你们可以做到的。
Don't use lights brighter than you need to. Don't use lights when you don't need them.
不要用过亮的光。当你们不需要的时候，就不要用。
Those lights you're using, make sure they're shielded down, so they're not shining up into the sky.
你们需要用的那些光，确保它们的上方是有屏障的，尽量不直接朝天空发光。
And let's talk about LED lights. If you have a choice, don't buy the blue ones. Look for words like "warm white."
我们来讲讲发光二极管。如果可以，尽量避免购买蓝色的。可以寻找带有“暖白光”字眼的灯泡。
If you buy LEDs with words like "natural light" or "daylight," that's like saying you hate space.
如果你购买的LED上有“自然光”或“日光”的标签，就等于说你讨厌太空。
And finally, you could advocate for this.
最后一点，你可以四处提倡这些“诀窍”。
Even in your local community, find out if there's a lighting code and whether it could be made more night-sky friendly.
即使在你的社区中，也可以试着找找有没有照明规范，若有的话，我们怎样能做得更好。
Or dare I say, you could even advocate at the federal level, by politely asking our federal officials, some of whom may be here,
我敢说你们甚至可以把问题提升到联邦级别，礼貌地问问我们的联邦官员，他们中的某些人可能就在这里，
to please not auction off our view of the invisible universe to the highest bidder to pollute at will, which is actually what happens.
请不要拍卖掉我们无形宇宙的景色，而让最高出价者随意污染，这其实也就是现在的情形。
Now, like a good professor, I have homework for you.
现在，就像一个优秀的教授一样，我要给你们留个功课。
If you have never seen a truly dark night sky, I want you to go out and experience one for yourself.
如果你们从来没有见过一个真正黑暗的夜空，我想让你们出去亲自体验一下。
Because if you don't, you don't know what you're missing, and you don't know what humanity is losing. Thank you.
因为如果没有过这样的体验，你就不知道你错过了什么，更不知道人类正在失去什么。谢谢！