The most detailed map of galaxies, black holes and stars ever made | Juna Kollmeier

翻译人员: Yolanda Zhang 校对人员: Bighead Ge

When I was a kid, I was afraid of the dark.

当我还是孩子时，我很惧怕黑暗。

The darkness is where the monsters are.

黑暗是怪兽出没的地方。

And I had this little night light outside of my bedroom

我的卧室外面有一盏小小的夜灯，

so that it would never get too dark.

这样我的房间就不会一片漆黑。

But over time, my fear of the dark turned to curiosity.

但是随着时间推移， 我对黑暗的恐惧变成了好奇。

What is out there in the "dark-dark?"

黑暗中都有什么？

And it turns out

我发现

that trying to understand the darkness is something that's fascinated humans

数千年来，人类一直在试图探索黑暗，

for thousands of years, maybe forever.

这种好奇心可能永远不会消逝。

And we know this

我们知道这一点，

because we find their ancient relics of their attempts to map the sky.

是因为我们找到了祖先们试图绘制 星空位置的古老遗迹。

This tusk is over 30,000 years old.

这只象牙已经有3万年的历史了。

Some people think that it's a carving of Orion

有些人认为这里雕刻的是猎户座，

or maybe a calendar.

也可能只是一个日历。

We don't know.

我们不知道。

The Fuxi star map is over 6,000 years old,

伏羲星图已有6000多年的历史，

and it's from a neolithic tomb in ancient China.

它来自中国一座新石器时代的古墓。

And that little pile of clamshells

中间那个死人脚下的

underneath the dead guy's foot in the middle --

一堆蛤壳——

that's supposed to be the Big Dipper.

应该是北斗七星。

Maybe.

也许是吧。

The Nebra disk is uncontroversial.

内布拉星象盘上的图案 更是一目了然。

You don't have to be an astronomer to know that you're looking at the Moon phases

即使你不是天文学家，也能认出

or the Sun in eclipse.

这图案代表月相或日食中的太阳。

And that little group of seven stars, that's the Pleiades, the Seven Sisters.

凑在一起的那七颗星 就是昴宿星，七姐妹星。

But in any case, the point is clear:

但无论如何，有一点是清楚的：

astronomers have been mapping the sky for a long time.

天文学家对天空进行测绘 已经有很长时间了。

Why?

他们为什么这么做呢？

It's our calling card as a species in the galaxy

这是我们作为星系中的一个物种

to figure things out.

来解决问题的标志。

We know our planet,

我们了解我们的星球，

we cure our diseases,

能治愈我们的疾病，

we cook our food,

会烹饪我们的食物，

we leave our planet.

甚至还能离开我们的星球进入太空。

But it's not easy.

但这并不容易。

Understanding the universe is battle.

探索宇宙是一场战斗。

It is unrelenting, it is time-varying,

充满艰辛，变幻无穷，

and it is one we are all in together.

我们所有人都置身其中。

It is a battle in the darkness against the darkness.

这是一场在黑暗中对抗黑暗的战斗。

Which is why Orion has weapons.

这就是猎户座拥有武器的原因。

In any case, if you're going to engage in this battle,

无论如何，如果你要参与这场战斗，

you need to know the battlefield.

就需要了解身处的战场。

So at its core,

测绘天空地图的

mapping the sky involves three essential elements.

核心包括三个基本要素。

You've got objects that are giving off light,

有发光的观测对象，

you've got telescopes that are collecting that light,

有收集光线的望远镜，

and you've got instruments

还有帮助你

that are helping you understand what that light is.

分析理解这些光线的仪器。

Many of you have mapped the Moon phases over time

我们当中很多人 都用眼睛观测过月相图，

with your eyes, your eyes being your more basic telescope.

眼睛是很基础的望远镜。

And you've understood what that means with your brains,

我们也理解了大脑 扮演着什么样的角色，

your brains being one of your more basic instruments.

大脑就是最基础的分析仪器。

Now, if you and a buddy get together,

如果你和一个朋友在一起，

you would spend over 30 years,

花费30多年的时间，

you would map 1,000 stars extremely precisely.

你就能绘制出1000 颗 恒星极其精确的图像。

You would move the front line to the battle.

你要把前线搬到战场上去。

And that's what Tycho Brahe and his buddy, or his assistant, really,

这就是第谷 · 布拉赫和他的伙伴， 确切的说是他的助手，

Johannes Kepler did back in the 1600s.

约翰尼斯 · 开普勒在17世纪所做的。

And they moved the line,

他们移动了这条线，

figured out how planets worked,

弄清楚了行星的运动轨迹，

how they moved around the Sun.

它们是如何围绕太阳运转的。

But it wasn't until about 100 years ago

但直到大约100年前，

that we realized

我们才意识到

it's a big universe.

这个宇宙很大。

It seems like the universe is just infinite, which it is,

宇宙看起来是无边无际的， 事实也确实如此，

but the observable universe is finite.

但是可观测的宇宙是有限的。

Which means we can win the battle.

这意味着我们可以赢得这场战斗。

But if you're going to map the universe,

但如果你要绘制宇宙地图，

you're not going to do it with one or two of your besties.

叫上一两个好朋友是不够的。

Mapping the universe takes an army,

绘制宇宙地图需要一支军队，

an army of curious, creative, craftspeople

一支充满好奇心、富有创造力、 技艺精湛的军队，

who, working together, can accomplish the extraordinary.

他们齐心协力， 就可以完成非凡的任务。

I lead this army of creatives,

我领导着这支创意大军，

in the fifth generation of the Sloan Digital Sky Survey, SDSS.

参加了第五代斯隆 数字巡天项目，简称SDSS。

And this is how astronomers have managed to shepherd individual curiosity

这就是天文学家们 如何在工业时代成功的：

through its industrial age,

他们激发了个人的好奇心，

preserving the individual ability to make discoveries

保留了个人探索的能力，

but putting into place mega machinery to truly advance the frontier.

同时投入巨大的机器来 真正推进探索的边界。

In SDSS, we divide the sky into three mappers:

在SDSS中，我们将天空 分割成三个探索区域：

one for the stars, one for the black holes

一个探索恒星，一个探索黑洞，

and one for the galaxies.

一个探索星系。

My survey has two hemispheres,

我的测绘范围包含两个半球，

five telescopes, or 11, depending on how you count,

5个望远镜，或者11个， 取决于你怎么计数，

10 spectrographs

10个摄谱仪

and millions of objects.

以及数百万个观测对象。

It's a monster.

这真是一个庞然大物。

So let's go through the mappers.

下面我们来看看这几个区域。

The Milky Way galaxy has 250 billion plus or minus a few hundred billion stars.

银河系有2500亿颗恒星， 误差可能有几千亿。

That is not a number that you hold in your head.

这个数字大到难以想象。

That is a number that doesn't make practical sense

这个数字对任何人来说

to pretty much anybody.

都没有实际意义。

You never get 250 billion jelly beans in your hand. You know?

生活中根本见不到这么大的数字。

We're nowhere near mapping all of those stars yet.

我们离测绘出所有这些 恒星的分布还差得远。

So we have to choose the most interesting ones.

所以我们必须聚焦最有趣的那些。

In SDSS-V, we're mapping six million stars

在SDSS-V中，我们正在 测绘600万颗恒星的图像，

我们认为可以测算它们的年龄。

where we think we can measure their age.

Because if you can measure the age of a star,

因为如果你能测算一颗恒星的年龄，

that's like having six million clocks spread all throughout the Milky Way.

那就像在银河系里分布着六百万个时钟。

And with that information,

有了这些信息，

we can unravel the history and fossil record of our galaxy

我们就可以揭开银河系的 历史和化石记录，

and learn how it formed.

了解它的起源。

I'm just going to cut right to the chase here.

我直接切入正题。

Black holes are among the most perplexing objects in the universe.

黑洞是宇宙中最令人困惑的物质之一。

Why?

为什么?

Because they are literally just math incarnate, in a physical form,

因为它们几乎是数学实体化的结果， 以一种我们几乎无法理解的

that we barely understand.

物理形式存在着。

It's like the number zero being animated and walking around the corridors here.

就像数字0的动画影像 在我们身边走来走去一样。

That would be super weird.

那太奇怪了。

These are weirder.

而黑洞的存在更令人匪夷所思。

And it's not just like a basketball

它不像一个篮球，

that you smoosh down into a little point and it's super dense and that's weird.

不是把它塞进一个小点， 密度就变得非常大。

No, smooshed basketballs have a surface.

被压缩的篮球好歹还有表面，

These things don't have surfaces, and we know that now.

这些东西没有表面， 我们现在已经知道黑洞这点了。

Because we've seen it.

因为我们见过黑洞，

Or the lack of it.

或者应该说，我们看到它没有表面。

What's really interesting about black holes

黑洞最有意思的地方在于，

is that we can learn a lot about them by studying the material

我们可以通过研究穿过一个

just as it passes through that point of no information return.

没有信息返回的点的 物质来充分了解黑洞。

Because at that point,

因为在那个点，

it's emitting lots of X-rays and optical and UV and radio waves.

该物质会发射出大量的X射线、 可见光、紫外线和无线电波。

We can actually learn how these objects grow.

我们可以知道这些黑洞是如何膨胀的。

And in SDSS, we're looking at over half a million supermassive black holes,

在SDSS中，我们观察了 超过50万个超大质量黑洞，

to try to understand how they formed.

试图了解它们是如何形成的。

Like I said,

就像我说的，

we live in the Milky Way, you guys are all familiar with that.

我们生活在银河系，你们都很熟悉。

The Milky Way is a completely average galaxy.

银河系是个十分普通的星系，

Nothing funny going on.

没有任何光怪陆离的现象。

But it's ours, which is great.

而这正是我们的家乡，这一点很不错。

We think that the Milky Way, and all the Milky Ways,

我们认为银河系，以及所有的银河系，

have this really disturbing past

在过去都发生了

of literally blowing themselves apart.

惊心动魄的爆炸。

It's like every average guy you know

就好比你认识的每个普通人

has a history as a punk rock teenager.

都曾是朋克摇滚的叛逆少年。

That's very bizarre.

这是非常奇怪的。

Stars are blowing up in these systems,

恒星在这些系统中爆炸，

black holes are growing at their centers

中心形成了黑洞，

and emitting a tremendous amount of energy.

并释放出巨大的能量。

How does that happen, how does this transformation happen?

这是怎么发生的， 这种变化是怎么发生的?

And at SDSS, we're going to the bellies of the beast

而在SDSS，我们要深入 这些星系怪物的内部，

and zooming way in,

一路上将观察到的景象放大，

to look at these processes where they are occurring

看看这些过程在哪里发生，

in order to understand how Sid Vicious grows up into Ward Cleaver.

以便了解恒星变成黑洞的过程。

My arsenal.

这些是我的研究设备。

These are my two big telescopes.

这是我的两个大望远镜。

The Apache Point Observatory hosts the Sloan telescope in New Mexico,

新墨西哥州的阿帕奇点天文台 拥有斯隆望远镜，

and the Las Campanas Observatory in Chile

智利的拉斯坎帕纳斯天文台

hosts the two-and-a-half-meter telescope, the du Pont.

拥有2.5米宽的杜邦望远镜。

Two and a half meters is the size of our mirror,

2.5米是我们镜子的大小，

which was huge for Tycho and Kepler.

这对第谷和开普勒来说是很大的，

But it's actually not so big today.

但是以今天的标准来看 它实际上没有那么大，

There are way bigger telescopes out there.

还有更大的望远镜。

But in SDSS we use new instruments on these old telescopes

但在SDSS中，我们在 这些旧望远镜上连接了新仪器，

to make them interesting.

使它们变得更有趣。

We capture light from all of those objects into our aperture,

我们把所有这些观测对象的 光都捕捉到光圈里，

and that light is then focused at the focal plane,

让这些光聚焦在焦平面上，

where our instruments sit and process that light.

我们的仪器就在那里处理这些光。

What's new in SDSS-V

SDSS-V 的创新之处

is that we're making the focal plane entirely robotic.

在于我们将焦平面完全变成了机器人。

That's right: robots.

没错：机器人。

(Laughter)

（笑声）

So I'm going to show them to you,

我要给你们看看，

but they're fierce and terrifying,

但是它们很凶猛，很可怕，

and I want you all to just take a breath.

我想让你们深呼吸做好准备。

(Exhales) Trigger warning.

（呼气）前方高能。

And with no apologies to all the Blade Runners among you,

胆子大的人也要小心，

here they are.

它们来了。

(Laughter)

（笑声）

I have 1,000 of these,

我有1000个这样的仪器，

有500个分布于每个半球的 每个望远镜的焦平面上。

500 in the focal plane of each telescope in each hemisphere.

And this is how they move on the sky.

这就是它们在天空中运动的方式。

So these are our objects and a star field,

这些是我们的观测对象和一个恒星场，

so you've got stars, galaxies, black holes.

这样就看到了恒星，星系，黑洞。

And our robots move to those objects as we pass over them

机器人移动到我们经过的 那些观测对象，

in order to capture the light

为了从这些恒星，星系和

from those stars and galaxies and black holes, and yes,

黑洞——是的，黑洞——捕捉光线。

it is weird to capture black hole light,

捕捉黑洞的光线很奇怪，

but we've already gone over that black holes are weird.

但我刚刚就说过 黑洞就是个奇怪的现象。

One more thing.

还有一件事。

Stars are exploding all the time,

恒星一直在爆炸，

like this one did back in 1987 in our cosmic backyard.

就像这颗1987年 在我们“宇宙后院”中爆炸的恒星。

Black holes are growing all the time.

黑洞的规模一直在变大。

There is a new sky every night.

天空在每天晚上都会焕然一新。

Which means we can't just map the sky one time.

这意味着我们不能只测绘一次，

We have to map the sky multiple times.

必须再反复几次。

So in SDSS-V, we're going back to each part of the sky multiple times

所以在SDSS-V中， 我们要多次回到天空的每个部分，

为了看看这些观测对象 是如何随着时间变化的。

in order to see how these objects change over time.

Because those changes in time encode the physics,

因为这些时间上的变化蕴含了物理原理，

and they encode how these objects are growing and changing.

蕴含了这些观测对象 形成和变化的秘密。

Mow the sky.

这一步就是“修整天空”。

OK, let me just recap.

现在我们来总结一下。

Global survey, two hemispheres,

全球巡视，两个半球，

five telescopes, 10 spectrographs, millions of objects, mow the sky,

5个望远镜，10个摄谱仪， 数以百万计的观测对象，“修整天空”，

creative army, robots, yeah.

创造性的军队，机器人，就是这些。

So you're thinking, "Wow.

你可能觉得不可思议。

She must have this industrial machine going,

她的团队一定是包揽了太空测绘工作，

no room for the individual, curious, lone wolf genius," right?

没有空间留给个人， 留给好奇的天才，对吧?

And you'd be 100 percent wrong.

那你就大错特错了。

Meet Hanny's Voorwerp.

来认识一下哈尼天体。

Hanny van Arkel was a Dutch schoolteacher

哈尼·冯·阿科尔 曾经是一名荷兰教师，

who was analyzing the public versions of the SDSS data,

她在分析SDSS数据的公共版本时，

when she found this incredibly rare type of object,

发现了这种极其罕见的星体形态，

which is now a subject of major study.

现在成为了我们的主要研究对象。

She was able to do this

她之所以能做到这一点，

because SDSS, since its beginning and by mandate from the Sloan Foundation,

是因为SDSS自成立以来， 根据斯隆基金会的授权，

has made its data both publicly available

已将其数据向大众公开，

and usable to a broad range of audiences.

广大群众都可以使用。

She's a citizen -- yeah, clap for that.

她只是个普通公民，很了不起，

Clap for that.

为她鼓掌吧。

(Applause)

（掌声）

哈尼是一个草根科学家，

Hanny is a citizen scientist,

or as I like to call them,

我喜欢叫他们这样的人

"citizen warriors."

“公民战士”。

And she shows that you don't have to be a fancy astrophysicist to participate.

她的例子说明你不需要成为 一个杰出天体物理学家也能参与其中。

You just have to be curious.

只需要保持好奇心。

A few years ago,

几年前，

我四岁的孩子问：“月亮也有月亮吗？”

my four-year-old asked, "Can moons have moons?"

And I set about to answer this question

我开始准备认真回答这个问题，

because even though many four-year-olds over all of time

因为尽管许多四岁左右的孩子

have probably asked this question,

一直都在问这个问题，

many experts, including myself, didn't know the answer.

但许多专家，包括我自己，都不知道答案。

These are the moons in our solar system that can host hypothetical submoons.

这些是我们太阳系中 可以容纳假想子卫星的卫星。

And that just goes to show you that there are so many basic questions

这只是告诉你们，还有很多基本问题

left to be understood.

需要去探索答案。

And this brings me to the most important point about SDSS.

这就引出了关于SDSS最重要的一点。

Because, yeah, the stars, the galaxies, the black holes, the robots --

没错，恒星，星系，黑洞，机器人——

that's all super cool.

这些都非常酷。

But the coolest thing of all

但最酷的是，

is that eensy-weensy creatures on a rubble pile

在一个非常普通的星系中，

around a totally average star in a totally average galaxy

围绕着一颗非常普通的恒星，

can win the battle to understand their world.

一群不起眼的生物（人类）在瓦砾堆上 能够赢得探索它们世界的战斗。

Every dot in this video is a galaxy.

这个视频中的每个点都是一个星系。

Every dot.

每一个点。

(Cheers) (Applause)

（欢呼） （掌声）

I'm showing here the number of galaxies

我在这里展示的是自1980年以来，

that astronomers have mapped in large surveys since about 1980.

天文学家在大型巡天过程中 测绘出的星系数量。

You can see SDSS kick in around Y2K.

你可以看到SDSS在2000年左右启动。

If we stay on this line,

如果我们继续沿着这条线走，

we will map every large galaxy in the observable universe by 2060.

到2060年我们将绘制出 可观测宇宙中每一个大星系的样貌。

Think about that.

想想看。

Think about it: we've gone from arranging clamshells

想想看吧：在几千年的时间里， 我们已经完成了从整理蛤壳

to general relativity to SDSS in a few thousand years --

到广义相对论， 再到整理SDSS的跨越——

and if we hang on 40 more,

如果我们再坚持40年，

we can map all the galaxies.

将可以绘制出所有星系的样貌。

But we have to stay on the line.

但前提是我们必须坚持下去。

Will that be our choice?

我们能做出这样的选择吗？

There are dark forces in this world

这个世界上有一些黑暗势力，

that will rob our entire species of our right to understand our universe.

它们将剥夺我们整个物种 理解宇宙的权利。

Don't be afraid of the dark.

不要惧怕黑暗。

Fight back.

反击。

Join us.

加入我们的行列。

Thank you.

谢谢大家！

(Applause)

（掌声）