TED2016
Tabetha Boyajian: The most mysterious star in the universe
Tabetha Boyajian: 宇宙中最诡异的恒星
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有个巨大的，差不多 1000 倍于地球面积的物体，正阻挡着来自遥远恒星 KIC 8462852 发出的光。没有人确切知道那是什么东西。天文学家 Tabetha Boyajian 讨论了这个巨大的、异常的天体可能是什么。一位同行提了一个不太寻常的建议：这有没有可能是外星人建造的巨大的超级建筑呢？如此非同寻常的想法需要非同寻常的证据来证实。在本次演讲中，Boyajian 讲述了作为科学家，面对未知如何搜寻并且检验假说的故事。
Tabetha Boyajian - Astronomer
Tabetha Boyajian is best known for her research on KIC 8462852, a puzzling celestial body that has inspired otherwise sober scientists to brainstorm outlandish hypotheses. Full bio
Tabetha Boyajian is best known for her research on KIC 8462852, a puzzling celestial body that has inspired otherwise sober scientists to brainstorm outlandish hypotheses. Full bio
Double-click the English transcript below to play the video.
00:12
Extraordinary claims
require extraordinary evidence,
require extraordinary evidence,
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非同寻常的结论
需要非同寻常的证据。
需要非同寻常的证据。
作为天文学家，
这是我的职责和责任
这是我的职责和责任
00:17
and it is my job,
my responsibility, as an astronomer
my responsibility, as an astronomer
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00:22
to remind people that alien hypotheses
should always be a last resort.
should always be a last resort.
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去提醒人们外星人假说
一直都该是最后一根救命稻草。
一直都该是最后一根救命稻草。
00:29
Now, I want to tell you
a story about that.
a story about that.
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现在，我要给你们
讲这么一个故事。
讲这么一个故事。
故事中有来自 NASA 项目中的数据，
00:31
It involves data from a NASA mission,
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有普通人，还有一颗
银河系里最非同寻常的星星。
银河系里最非同寻常的星星。
00:35
ordinary people and one of the most
extraordinary stars in our galaxy.
extraordinary stars in our galaxy.
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00:41
It began in 2009 with the launch
of NASA's Kepler mission.
of NASA's Kepler mission.
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故事开始于 2009 年，
NASA 启动了开普勒计划。
NASA 启动了开普勒计划。
00:46
Kepler's main scientific objective
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开普勒计划的
首要科学目标
首要科学目标
是寻找太阳系以外的行星。
00:48
was to find planets
outside of our solar system.
outside of our solar system.
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它持续观测一小块天区，
00:51
It did this by staring
at a single field in the sky,
at a single field in the sky,
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就这块，所有这些小方块。
00:54
this one, with all the tiny boxes.
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00:57
And in this one field,
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在这小块区域中，
00:58
it monitored the brightness
of over 150,000 stars
of over 150,000 stars
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它持续观测超过
15 万颗恒星的亮度，
15 万颗恒星的亮度，
整整四年，
01:03
continuously for four years,
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每 30 分钟就采集一次数据。
01:05
taking a data point every 30 minutes.
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01:10
It was looking for what
astronomers call a transit.
astronomers call a transit.
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它在搜寻天文学家
叫做掩食的东西。
叫做掩食的东西。
它发生在行星轨道和
我们的观测视线重合情况。
我们的观测视线重合情况。
01:13
This is when the planet's orbit
is aligned in our line of sight,
is aligned in our line of sight,
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这样，行星就会
从恒星前面经过。
从恒星前面经过。
01:18
just so that the planet
crosses in front of a star.
crosses in front of a star.
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这种情况下，行星
就会挡住一点点的星光。
就会挡住一点点的星光。
01:22
And when this happens,
it blocks out a tiny bit of starlight,
it blocks out a tiny bit of starlight,
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你可以在光度曲线上
看到小小的负峰。
看到小小的负峰。
01:27
which you can see as a dip in this curve.
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01:31
And so the team at NASA
had developed very sophisticated computers
had developed very sophisticated computers
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于是 NASA 团队开发出
非常复杂的电脑程序，
非常复杂的电脑程序，
来搜寻开普勒
数据中的掩食事件。
数据中的掩食事件。
01:36
to search for transits
in all the Kepler data.
in all the Kepler data.
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01:40
At the same time
of the first data release,
of the first data release,
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在首次数据发布的同时，
耶鲁大学的天文学家
在考虑一个有趣的问题：
在考虑一个有趣的问题：
01:44
astronomers at Yale
were wondering an interesting thing:
were wondering an interesting thing:
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01:48
What if computers missed something?
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万一电脑错过了什么怎么办？
01:53
And so we launched the citizen
science project called Planet Hunters
science project called Planet Hunters
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于是，我们又发起了一项
名为“行星猎人”的公民科学项目。
名为“行星猎人”的公民科学项目。
01:57
to have people look at the same data.
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这个项目依靠大众
来分析同样的数据。
来分析同样的数据。
02:01
The human brain has an amazing ability
for pattern recognition,
for pattern recognition,
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人脑有着惊人的模式识别能力，
有时候甚至比电脑都厉害。
02:05
sometimes even better than a computer.
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然而，这个项目
遭到了很多质疑。
遭到了很多质疑。
02:07
However, there was a lot
of skepticism around this.
of skepticism around this.
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我的同行，黛布拉·费舍尔，
行星猎人项目的发起人，
行星猎人项目的发起人，
02:10
My colleague, Debra Fischer,
founder of the Planet Hunters project,
founder of the Planet Hunters project,
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说那时候人们议论道：
02:13
said that people at the time were saying,
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“你们疯了。
电脑绝不可能错过信号。”
电脑绝不可能错过信号。”
02:15
"You're crazy. There's no way
that a computer will miss a signal."
that a computer will miss a signal."
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02:19
And so it was on, the classic
human versus machine gamble.
human versus machine gamble.
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所以这又是人和机器
赌哪个的老段子。
赌哪个的老段子。
如果我们发现了一颗行星，
那我们就会特别高兴。
那我们就会特别高兴。
02:23
And if we found one planet,
we would be thrilled.
we would be thrilled.
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四年前，
在我加入这个团队的时候，
在我加入这个团队的时候，
02:27
When I joined the team four years ago,
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我们已经有了发现。
02:29
we had already found a couple.
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02:32
And today, with the help
of over 300,000 science enthusiasts,
of over 300,000 science enthusiasts,
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而今天，通过超过 30 万
科学爱好者的努力，
科学爱好者的努力，
我们已经发现了数十颗行星，
02:37
we have found dozens,
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而且我们发现了
这一颗银河系中
这一颗银河系中
02:38
and we've also found
one of the most mysterious stars
one of the most mysterious stars
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最最奇异的恒星。
02:42
in our galaxy.
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02:45
So to understand this,
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为了说清楚，
请看一下开普勒数据中
一次正常的掩食是什么样子。
一次正常的掩食是什么样子。
02:46
let me show you what a normal transit
in Kepler data looks like.
in Kepler data looks like.
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02:50
On this graph on the left-hand side
you have the amount of light,
you have the amount of light,
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这幅图中，左边轴是光强度，
底下的横轴是时间。
02:54
and on the bottom is time.
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这条白线是单纯来自恒星的光，
02:55
The white line
is light just from the star,
is light just from the star,
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天文学家称为光度曲线。
02:59
what astronomers call a light curve.
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现在，当一颗行星掩过恒星，
它阻挡了一点点星光，
它阻挡了一点点星光，
03:01
Now, when a planet transits a star,
it blocks out a little bit of this light,
it blocks out a little bit of this light,
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而这个掩食的深度
反映了行星体自身的大小。
反映了行星体自身的大小。
03:05
and the depth of this transit
reflects the size of the object itself.
reflects the size of the object itself.
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所以，例如木星。
03:10
And so, for example, let's take Jupiter.
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行星通常不太会
比木星还要大。
比木星还要大。
03:13
Planets don't get
much bigger than Jupiter.
much bigger than Jupiter.
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木星会减弱百分之一的星光。
03:15
Jupiter will make a one percent drop
in a star's brightness.
in a star's brightness.
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换做地球，
地球只有木星的 1/11 大，
地球只有木星的 1/11 大，
03:19
Earth, on the other hand,
is 11 times smaller than Jupiter,
is 11 times smaller than Jupiter,
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它的信号在数据中几乎看不见。
03:23
and the signal
is barely visible in the data.
is barely visible in the data.
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03:26
So back to our mystery.
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回到我们的谜题。
03:28
A few years ago, Planet Hunters were
sifting through data looking for transits,
sifting through data looking for transits,
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几年前，行星猎人
正在筛选数据寻找掩食，
正在筛选数据寻找掩食，
03:33
and they spotted a mysterious signal
coming from the star KIC 8462852.
coming from the star KIC 8462852.
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他们发现了一个诡异的信号
来自恒星 KIC 8462852。
来自恒星 KIC 8462852。
03:39
The observations in May of 2009
were the first they spotted,
were the first they spotted,
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2009 年五月是他们
首次发现这个信号，
首次发现这个信号，
他们开始在论坛中
讨论这个发现。
讨论这个发现。
03:43
and they started talking about this
in the discussion forums.
in the discussion forums.
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03:47
They said and object like Jupiter
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他们说一个类似木星的星体
可以造成这样的星光削弱，
03:49
would make a drop like this
in the star's light,
in the star's light,
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但他们也说这家伙太大了。
03:52
but they were also saying it was giant.
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你看，掩食通常只持续几个小时，
03:55
You see, transits normally
only last for a few hours,
only last for a few hours,
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而这一个持续了将近一周。
03:58
and this one lasted for almost a week.
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04:01
They were also saying
that it looks asymmetric,
that it looks asymmetric,
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他们也在说谱线看起来不对称，
这是说，不像木星那样
有一个干净、U 型的负峰，
有一个干净、U 型的负峰，
04:05
meaning that instead of the clean,
U-shaped dip that we saw with Jupiter,
U-shaped dip that we saw with Jupiter,
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大家看，这条数据左侧
的倾斜度很奇怪。
的倾斜度很奇怪。
04:09
it had this strange slope
that you can see on the left side.
that you can see on the left side.
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这似乎意味着，
04:13
This seemed to indicate
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无论闯进来
挡住星光的是什么东西，
挡住星光的是什么东西，
04:14
that whatever was getting in the way
and blocking the starlight
and blocking the starlight
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它不会像行星那样是个球形。
04:18
was not circular like a planet.
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04:21
There are few more dips that happened,
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后来陆续还有少量的负峰，
04:23
but for a couple of years,
it was pretty quiet.
it was pretty quiet.
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但这颗星在之后的一两年
一直都没什么动静。
一直都没什么动静。
04:26
And then in March of 2011, we see this.
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然后在 2011 年三月，
我们观察到了这个。
我们观察到了这个。
04:31
The star's light drops
by a whole 15 percent,
by a whole 15 percent,
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这颗恒星的光度
掉了整整 15%，
掉了整整 15%，
这比一颗行星能造成的大太多了，
04:35
and this is huge compared to a planet,
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行星只能造成 1% 的光度下降。
04:37
which would only make a one percent drop.
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04:40
We described this feature
as both smooth and clean.
as both smooth and clean.
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我们把这条谱线特征
描述为光滑和干净。
描述为光滑和干净。
它也是不对称的，
04:44
It also is asymmetric,
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在持续近一周的时间内
逐步减弱，
逐步减弱，
04:46
having a gradual dimming
that lasts almost a week,
that lasts almost a week,
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然后在一两天内
立马反弹回正常的光度。
立马反弹回正常的光度。
04:48
and then it snaps right back up to normal
in just a matter of days.
in just a matter of days.
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04:52
And again, after this, not much happens
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在此之后，又是什么都没发生，
直到 2013 年二月。
04:57
until February of 2013.
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事情的发展完全出乎意料。
05:00
Things start to get really crazy.
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光度曲线上出现了
一大群复杂的负峰，
一大群复杂的负峰，
05:03
There is a huge complex of dips
in the light curve that appear,
in the light curve that appear,
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而且它们持续了
差不多一百天，
差不多一百天，
05:08
and they last for like a hundred days,
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一直延续到
开普勒计划结束。
开普勒计划结束。
05:10
all the way up
into the Kepler mission's end.
into the Kepler mission's end.
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05:13
These dips have variable shapes.
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这些负峰有着各种形状。
有一些很尖锐，
有一些很宽，
有一些很宽，
05:15
Some are very sharp, and some are broad,
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以及有不同的持续时间。
05:17
and they also have variable durations.
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有一些只持续一两天，
有的则超过一周。
有的则超过一周。
05:19
Some last just for a day or two,
and some for more than a week.
and some for more than a week.
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05:24
And there's also up and down trends
within some of these dips,
within some of these dips,
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而且在一些光度负峰中，
还出现上上下下的起伏，
还出现上上下下的起伏，
感觉好像是几个独立事件
重叠在一起。
重叠在一起。
05:27
almost like several independent events
were superimposed on top of each other.
were superimposed on top of each other.
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05:32
And at this time, this star drops
in its brightness over 20 percent.
in its brightness over 20 percent.
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而且这次，这颗恒星的亮度
下降了超过 20%。
下降了超过 20%。
这说明不管是什么东西
挡住了光，
挡住了光，
05:39
This means that whatever
is blocking its light
is blocking its light
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这家伙有着超过地球
1000 倍的面积。
1000 倍的面积。
05:41
has an area of over 1,000 times
the area of our planet Earth.
the area of our planet Earth.
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05:46
This is truly remarkable.
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这真心是非同寻常。
05:49
And so the citizen scientists,
when they saw this,
when they saw this,
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当公民科学家发现这个时，
他们通知了科学家团队，
称他们发现了足够奇怪的东西
称他们发现了足够奇怪的东西
05:51
they notified the science team
that they found something weird enough
that they found something weird enough
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可能值得后续跟进研究。
05:55
that it might be worth following up.
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05:58
And so when the science team looked at it,
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于是当科学家团队看过数据之后，
我们觉得：“好吧，会不会
只是数据有点问题。”
只是数据有点问题。”
06:00
we're like, "Yeah, there's probably
just something wrong with the data."
just something wrong with the data."
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不过经过我们非常、
非常、非常仔细的调查，
非常、非常仔细的调查，
06:04
But we looked really, really, really hard,
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06:06
and the data were good.
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数据没有问题。
06:10
And so what was happening
had to be astrophysical,
had to be astrophysical,
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因此，出现这些负峰一定有
天体物理学的原因，
天体物理学的原因，
说明太空中有什么东西
经过了我们和恒星之间，
经过了我们和恒星之间，
06:13
meaning that something in space
was getting in the way
was getting in the way
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挡住了它的光。
06:17
and blocking starlight.
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06:20
And so at this point,
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这个时候，
我们竭力研究
关于这颗恒星的一切，
关于这颗恒星的一切，
06:21
we set out to learn
everything we could about the star
everything we could about the star
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希望能找到任何
可以解释这些现象的线索。
可以解释这些现象的线索。
06:24
to see if we could find any clues
to what was going on.
to what was going on.
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06:27
And the citizen scientists
who helped us in this discovery,
who helped us in this discovery,
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帮助我们发现这颗星的
公民科学家，
公民科学家，
也加入了讨论，
06:30
they joined along for the ride
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见证科学第一线的行动。
06:32
watching science in action firsthand.
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06:37
First, somebody said, you know,
what if this star was very young
what if this star was very young
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首先，有人提出，
是不是这颗星非常年轻，
是不是这颗星非常年轻，
它仍旧保有它诞生之时
周围的星际云物质。
周围的星际云物质。
06:42
and it still had the cloud of material
it was born from surrounding it.
it was born from surrounding it.
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06:47
And then somebody else said,
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另外有人说，
好吧，是不是这颗星
已经形成了行星系统，
已经形成了行星系统，
06:48
well, what if the star
had already formed planets,
had already formed planets,
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而两颗行星相撞了，
06:51
and two of these planets had collided,
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就像地球——月球的形成过程。
06:53
similar to the Earth-Moon forming event.
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06:56
Well, both of these theories
could explain part of the data,
could explain part of the data,
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好吧，这两种假说
都可以解释部分数据，
都可以解释部分数据，
但是困难在于，这颗恒星
没有显示任何年轻的特征，
没有显示任何年轻的特征，
07:00
but the difficulties were that the star
showed no signs of being young,
showed no signs of being young,
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而且也没有来自任何物质
07:03
and there was no glow
from any of the material
from any of the material
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被星光加热发出的光晕。
07:06
that was heated up by the star's light,
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如果恒星年轻，
07:08
and you would expect this
if the star was young
if the star was young
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或者碰撞产生大量尘埃，
通常会出现这种现象。
通常会出现这种现象。
07:11
or if there was a collision
and a lot of dust was produced.
and a lot of dust was produced.
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07:15
And so somebody else said,
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又有人说，
好吧，会不会是一大群彗星呢
07:17
well, how about a huge swarm of comets
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在一个非常椭圆的轨道上
一连串地穿过这颗恒星？
一连串地穿过这颗恒星？
07:22
that are passing by this star
in a very elliptical orbit?
in a very elliptical orbit?
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好吧，这个假说倒是
和我们的观测相吻合。
和我们的观测相吻合。
07:26
Well, it ends up that this is actually
consistent with our observations.
consistent with our observations.
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07:32
But I agree, it does feel
a little contrived.
a little contrived.
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但是我同意，
这感觉有点牵强。
这感觉有点牵强。
你看，需要数百颗彗星，
07:35
You see, it would take hundreds of comets
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才能重现我们的观测。
07:38
to reproduce what we're observing.
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07:41
And these are only the comets
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而这些只是
恰好从我们和恒星
中间穿过的彗星。
中间穿过的彗星。
07:42
that happen to pass
between us and the star.
between us and the star.
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所以实际情况下，
将会有成千上万颗彗星。
将会有成千上万颗彗星。
07:45
And so in reality, we're talking
thousands to tens of thousands of comets.
thousands to tens of thousands of comets.
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但是在我们所有的烂解释中，
07:51
But of all the bad ideas we had,
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这个算是最好的了。
07:55
this one was the best.
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于是我们发表了我们的发现。
07:57
And so we went ahead
and published our findings.
and published our findings.
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要我说，这是我写过的
最困难的论文之一。
最困难的论文之一。
08:00
Now, let me tell you, this was one
of the hardest papers I ever wrote.
of the hardest papers I ever wrote.
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科学家理应发表明确的结果，
08:04
Scientists are meant to publish results,
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而这次我们离结果
还有十万八千里呢。
还有十万八千里呢。
08:07
and this situation was far from that.
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08:09
And so we decided
to give it a catchy title,
to give it a catchy title,
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所以我们决定
起一个抓眼球的标题，
起一个抓眼球的标题，
我们的题目是：
《光去了哪里》
《光去了哪里》
08:13
and we called it: "Where's The Flux?"
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08:15
I will let you work out the acronym.
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麻烦大家自行意会这个梗
08:18
(Laughter)
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（笑声。标题的英文缩写为
WTF，即“什么鬼”）
WTF，即“什么鬼”）
08:22
So this isn't the end of the story.
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不过这故事还没完呢。
在我写这篇论文的同时，
08:24
Around the same time
I was writing this paper,
I was writing this paper,
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我见了一位同行，
贾森·莱特
贾森·莱特
08:26
I met with a colleague
of mine, Jason Wright,
of mine, Jason Wright,
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他也在写一篇
有关开普勒数据的论文。
有关开普勒数据的论文。
08:28
and he was also writing a paper
on Kepler data.
on Kepler data.
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他说道，从开普勒
无与伦比的精度来看，
无与伦比的精度来看，
08:31
And he was saying that with Kepler's
extreme precision,
extreme precision,
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它其实可以探测到
恒星周围的外星人建筑，
恒星周围的外星人建筑，
08:35
it could actually detect
alien megastructures around stars,
alien megastructures around stars,
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但是并没有发现。
08:40
but it didn't.
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08:42
And then I showed him this weird data
that our citizen scientists had found,
that our citizen scientists had found,
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然后我给他看了这个由我们
公民科学家发现的奇怪数据，
公民科学家发现的奇怪数据，
08:47
and he said to me,
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然后他对我说，
“见鬼，塔碧。
08:48
"Aw crap, Tabby.
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这下我论文得重写了。”
08:50
Now I have to rewrite my paper."
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08:54
So yes, the natural
explanations were weak,
explanations were weak,
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所以，没错，
自然解释很牵强，
自然解释很牵强，
08:58
and we were curious now.
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我们很好奇。
我们必须找到一个
排除外星人的方法。
排除外星人的方法。
09:00
So we had to find a way
to rule out aliens.
to rule out aliens.
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于是我俩一起说服了
09:03
So together, we convinced
a colleague of ours
a colleague of ours
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我们在 SETI（寻找地外
文明计划）工作的一位同行，
文明计划）工作的一位同行，
09:06
who works on SETI, the Search
for Extraterrestrial Intelligence,
for Extraterrestrial Intelligence,
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说这是一个非常
出色的追逐目标。
出色的追逐目标。
09:09
that this would be
an extraordinary target to pursue.
an extraordinary target to pursue.
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09:14
We wrote a proposal to observe the star
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我们起草了一份
观测这颗恒星的项目书
观测这颗恒星的项目书
请求使用绿岸天文台的
世界上最大的射电天文望远镜。
世界上最大的射电天文望远镜。
09:16
with the world's largest radio telescope
at the Green Bank Observatory.
at the Green Bank Observatory.
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两三个月后，
09:21
A couple months later,
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这份项目书的消息
被媒体刺探到了
被媒体刺探到了
09:22
news of this proposal
got leaked to the press
got leaked to the press
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09:27
and now there are thousands of articles,
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好吧，现在有几千篇报道
可能超过一万篇，
单单关于这颗恒星。
单单关于这颗恒星。
09:31
over 10,000 articles, on this star alone.
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如果你用谷歌图片搜索，
09:34
And if you search Google Images,
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09:36
this is what you'll find.
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你会找到这些。
09:39
Now, you may be wondering,
OK, Tabby, well,
OK, Tabby, well,
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现在，观众可能会问，
好吧塔碧，
好吧塔碧，
究竟怎么用外星人
去解释这光度曲线？
去解释这光度曲线？
09:42
how do aliens actually explain
this light curve?
this light curve?
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好吧，想象一个
远比我们发达的文明，
远比我们发达的文明，
09:46
OK, well, imagine a civilization
that's much more advanced than our own.
that's much more advanced than our own.
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在这个假设条件下，
09:51
In this hypothetical circumstance,
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09:54
this civilization would have exhausted
the energy supply of their home planet,
the energy supply of their home planet,
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这个文明肯定耗尽了
他们母星的能源。
他们母星的能源。
所以他们从哪里
获取更多的能量？
获取更多的能量？
09:59
so where could they get more energy?
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你看，他们有一颗宿主恒星，
就像我们有太阳一样，
就像我们有太阳一样，
10:01
Well, they have a host star
just like we have a sun,
just like we have a sun,
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10:05
and so if they were able
to capture more energy from this star,
to capture more energy from this star,
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那如果他们能够
从恒星中抓取更多能量，
从恒星中抓取更多能量，
那就可以解决
他们的能源需求。
他们的能源需求。
10:09
then that would solve their energy needs.
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10:11
So they would go
and build huge structures.
and build huge structures.
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所以他们可能会去
建造这些巨型建筑。
建造这些巨型建筑。
这些巨大的超级建筑，
10:15
These giant megastructures,
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比如巨大的太阳能电池板，
叫做“戴森球”。
叫做“戴森球”。
10:18
like ginormous solar panels,
are called Dyson spheres.
are called Dyson spheres.
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10:22
This image above
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上面这些图片
是许多艺术家想象中的戴森球。
10:23
are lots of artists' impressions
of Dyson spheres.
of Dyson spheres.
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很难去想象这些东西
究竟有多庞大，
究竟有多庞大，
10:26
It's really hard to provide perspective
on the vastness of these things,
on the vastness of these things,
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但你可以这么想。
10:32
but you can think of it this way.
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地球——月球间的距离
是四十万公里。
是四十万公里。
10:33
The Earth-Moon distance
is a quarter of a million miles.
is a quarter of a million miles.
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10:38
The simplest element
on one of these structures
on one of these structures
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这些巨型结构中的
最简单的单元，
最简单的单元，
是 100 倍地月距离。
10:41
is 100 times that size.
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10:45
They're enormous.
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它们是庞然大物。
10:48
And now imagine one of these structures
in motion around a star.
in motion around a star.
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再想象，这样一个建筑
围绕着一颗恒星运动。
围绕着一颗恒星运动。
你可以看到这为什么
可以造成数据中异常
可以造成数据中异常
10:52
You can see how it would produce
anomalies in the data
anomalies in the data
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如此不对称，不自然的负峰。
10:55
such as uneven, unnatural looking dips.
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但是即使是
外星人的超级建筑，
外星人的超级建筑，
10:58
But it remains that even
alien megastructures
alien megastructures
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也不能违反物理定律。
11:02
cannot defy the laws of physics.
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任何使用大量能量的东西
11:05
You see, anything that uses
a lot of energy
a lot of energy
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11:09
is going to produce heat,
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将会产生热量，
11:12
and we don't observe this.
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但是我们没有观测到。
但这有可能只是非常简单的，
11:14
But it could be something as simple
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11:16
as they're just reradiating it away
in another direction,
in another direction,
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他们把热量释放到了另一个方向，
11:20
just not at Earth.
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没有对着地球。
11:23
Another idea that's one
of my personal favorites
of my personal favorites
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我个人最喜欢的
另一种可能性是
另一种可能性是
11:26
is that we had just witnessed
an interplanetary space battle
an interplanetary space battle
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我们恰好目睹了
一场星球大战，
一场星球大战，
一颗行星被灾难性地
彻底摧毁了。
彻底摧毁了。
11:30
and the catastrophic
destruction of a planet.
destruction of a planet.
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11:34
Now, I admit that this
would produce a lot of dust
would produce a lot of dust
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我承认，
这会产生很多尘埃，
这会产生很多尘埃，
然而我们没有观测到。
11:37
that we don't observe.
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但是如果我们已经
在用外星人来解释，
在用外星人来解释，
11:39
But if we're already invoking aliens
in this explanation,
in this explanation,
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那谁说他们不会秋风扫落叶
一般清理干净尘埃，
一般清理干净尘埃，
11:44
then who is to say they didn't
efficiently clean up all this mess
efficiently clean up all this mess
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回收利用？
11:47
for recycling purposes?
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（笑声）
11:49
(Laughter)
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1016
你看，这很快
就激发想象力啦。
就激发想象力啦。
11:50
You can see how this quickly
captures your imagination.
captures your imagination.
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11:55
Well, there you have it.
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好啦，故事就是这样。
11:57
We're in a situation that could unfold
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我们的处境是，
既可以解释成
我们没搞清楚的自然现象，
我们没搞清楚的自然现象，
12:00
to be a natural phenomenon
we don't understand
we don't understand
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又可以解释成
我们没搞清楚的外星人科技。
我们没搞清楚的外星人科技。
12:03
or an alien technology
we don't understand.
we don't understand.
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12:07
Personally, as a scientist,
my money is on the natural explanation.
my money is on the natural explanation.
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作为科学家，我个人
还是会赌这是个自然现象。
还是会赌这是个自然现象。
12:14
But don't get me wrong, I do think
it would be awesome to find aliens.
it would be awesome to find aliens.
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但是别误解了，我绝对认同
能找到外星人非常棒。
能找到外星人非常棒。
不管怎样，有新东西，
非常有趣的东西等待发现。
非常有趣的东西等待发现。
12:18
Either way, there is something new
and really interesting to discover.
and really interesting to discover.
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12:24
So what happens next?
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那么，接下来呢？
12:25
We need to continue to observe this star
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我们需要继续观测这颗恒星
去更详细地了解发生了什么。
12:28
to learn more about what's happening.
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12:31
But professional astronomers, like me,
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然而，像我这样的职业天文学家，
12:33
we have limited resources
for this kind of thing,
for this kind of thing,
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我们在这方面的资源有限。
而开普勒望远镜已经在
执行另一项计划了。
执行另一项计划了。
12:36
and Kepler is on to a different mission.
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12:39
And I'm happy to say that once again,
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所以我很高兴地说，又一次，
公民科学家加入进来救场。
12:43
citizen scientists have come in
and saved the day.
and saved the day.
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12:47
You see, this time,
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你看，这次，
12:50
amateur astronomers
with their backyard telescopes
with their backyard telescopes
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业余天文爱好者
拿着他们的业余望远镜
拿着他们的业余望远镜
立刻加入进来，
开始在自己的观测点
开始在自己的观测点
12:54
stepped up immediately
and started observing this star nightly
and started observing this star nightly
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夜观此星。
12:58
at their own facilities,
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我非常期待他们的发现。
12:59
and I am so excited to see what they find.
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13:03
What's amazing to me is that this star
would have never been found by computers
would have never been found by computers
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对我来说，激动人心的是
这颗恒星可能根本不会被电脑发现，
这颗恒星可能根本不会被电脑发现，
13:07
because we just weren't looking
for something like this.
for something like this.
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因为我们单纯没有把
这样的恒星当成目标。
这样的恒星当成目标。
13:11
And what's more exciting
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更激动人心的是，
13:15
is that there's more data to come.
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将来还有更多的数据。
13:18
There are new missions that are coming up
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有新的观测项目要上马，
准备观测百万颗恒星，
13:20
that are observing millions more stars
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13:23
all over the sky.
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布满全天。
13:26
And just think: What will it mean
when we find another star like this?
when we find another star like this?
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思考一下：如果我们又找到
一颗这样的恒星，意味着什么？
一颗这样的恒星，意味着什么？
13:32
And what will it mean
if we don't find another star like this?
if we don't find another star like this?
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而如果我们一颗都没找到，
那又意味着什么？
那又意味着什么？
谢谢。
13:37
Thank you.
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（掌声）
13:38
(Applause)
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ABOUT THE SPEAKER
Tabetha Boyajian - AstronomerTabetha Boyajian is best known for her research on KIC 8462852, a puzzling celestial body that has inspired otherwise sober scientists to brainstorm outlandish hypotheses.
Why you should listen
Planet hunter Tabetha Boyajian studies KIC 8462852 (dubbed "Tabby's star" after her team's research): a star exhibiting bizarre (and thus far unique) variations in brightness. These fluctuations have led scientists to postulate causes ranging from comet dust (Boyajian's most likely scenario) to alien megastructures. The latest studies of Tabby's star have proved even more baffling: KIC 8462852 has been gradually dimming over the last century, a strikingly short period of time on an astronomical scale.
Boyajian currently serves as a postdoc with the Yale Exoplanet group, whose research is assisted by the Planet Hunters -- a citizen science group that combs data from the NASA Kepler Space Mission for evidence of exoplanets and other unusual interstellar activity.
More profile about the speakerBoyajian currently serves as a postdoc with the Yale Exoplanet group, whose research is assisted by the Planet Hunters -- a citizen science group that combs data from the NASA Kepler Space Mission for evidence of exoplanets and other unusual interstellar activity.
Tabetha Boyajian | Speaker | TED.com