- A+
Suddenly,Pluto was all Americans were talking about.
突然 冥王星成为所有美国人谈论的话题
Or rather, yelling about.
或者说 争论的对象
Some people were so angry, they were giving astronomers
一些人特别生气 他们给了天文学家
death threats.
死亡恐吓
– People were so angry that they said that
愤怒的人们说
all the astronomers should be put on the wall and shot at.
所有的天文学家应该被钉在墙上 作为活靶
– [Narrator] That’s Thierry Montmerle.
这是Thierry Montmerle
He’s former general secretary for the International Astronomical Union.
他是国际天文联合会的前任秘书长
The same organization of the world’s astronomers
他所在组织的世界天文学家们
that changed Pluto’s status from planet to dwarf planet in 2006.
在2006将冥王星的地位从行星改为矮行星
And today, over 12 years later,
今天 也就是12年后
people still have strong opinions whenever you ask
每当问起 冥王星应该重新成为一颗行星吗？
Should pluto be a plant again?
人们对此仍有强烈争议
– No.
不应该
– Yes.
应该
– No.
不应该
– No.
不应该
– Yeah.
当然应该了
– Yes.
应该的
– No.
哪能呢
– Yes.
必须应该
– I’m not really sure that I have an opinion
关于冥王星是否应该是一颗行星
of whether or not Pluto should be a planet.
我不太确定我对此有自己的看法
– [Narrator] There’s obviously some confusion going on 
here.
这里肯定存在一些困惑
So we did the next logical step.
所以我们采取了合乎逻辑的对策
We went to the experts to settle this once and for all.
我们寻找专家彻底解决这个问题
That’s Alan Stern.
这是Alan Stern
He leads NASA’s New Horizons mission,
他领导着的NASA“新视野号”任务
which flew by Pluto in 2015.
这个飞行器于2015年低空飞过冥王星
– And in planetary science where the experts in planets are
在行星科学 即行星的专家们所在的领域
we call small planets”planets.”
我们将小星球称作行星
We call large moons”planets.”
我们将大卫星也称作行星
We call all the planets around other stars”planets.”
我们称其他恒星周围的所有行星为行星
And the astronomer’s definition
可天文学家的定义
wouldn’t allow any of those to be planets.
绝不会允许上述任何星球被称为行星
– [Narrator] OK, so basically Stern says
好吧 所以Stern说的是
it depends on context.
这个基本上取决于讨论的场合
But why?
这是为什么嘞
Back in the early’90s, Pluto was a planet, period.
回到90年代初 冥王星是个行星 无异议
No context needed.
不会
因为所处讨论场合不同而变化
So what changed?
所以什么改变了这个状况呢？
By the late’90s, it was becoming clear
在90年代末 这个问题变得清晰了
that Pluto wasn’t alone.
冥王星并不孤独
Astronomers had discovered other worlds in the same region
天文学家在同一地区发现了其他领域
called the Kuiper belt.
被称为柯伊伯带的区域
And some of them looked awfully similar to Pluto.
其中一些星球看起来和冥王星非常相似
Then in 2005, astronomers discovered Eris,
之后在2005年 宇航员发现了阋神星
which estimates at the time suggested was even larger than Pluto.
当时人们估计这颗星球甚至比冥王星还要大
– On January 8 of this year, while looking through some old data that we had taken with the
这年的1月8日 当我们在浏览巴乐马山天文台
Samuel Oschin Telescope at Palomar Observatory,
塞缪尔·奥斯钦望远镜得到的旧数据时
we found, much to our surprise
我们发现了出乎意料的东西
an object, three times further away than Pluto.
有一个物体 比冥王星还要远三倍
This will absolutely rewrite the history of astronomy textbooks.
这无疑会改写天文学历史教科书
– [Narrator] And while these new worlds looked and behaved like Pluto,
虽然这些新的世界看起来和表现得都像冥王星
they were completely different from every other planet in our solar system.
但它们与太阳系里面的其它行星完全不同
Something had to be done.
有些事情必须得做
It was clear that astronomers were in need of something they never had before:
天文学家们很清楚他们需要一些前所未有的东西
a good definition for what makes a planet a planet.
一个能完整地说明某个星球是行星的定义
So in the wake of these new discoveries,
于是随着研究的发展
the IAU came up with a checklist.
国际天文联合会列出了一个清单
A planet must orbit the sun,
行星必须绕着太阳而行
have a nearly round shape,
呈近似圆形
and have cleared its neighborhood,
且周边干净
meaning no other large objects are nearby.
意味着周边没有其他大型物体
And the last requirement boots Pluto off the team of planet
最后一条要求 把冥王星逐出了行星的队伍
Yes, it orbits the sun.
它的确绕太阳转
Yes, it’s spherical.
它也确实是球形的
But Pluto isn’t always the dominant gravitational force in its neighborhood.
但冥王星并不总是其附近区域的主导引力
For one thing, Eris shares the region
比如说 阋神星与它共享一片领域
and isn’t stuck in Pluto’s orbit.
而且不在冥王星的轨道上
The end result?
结果呢
Pluto bumped from”planet” to”dwarf planet.”
冥王星从行星跌落为矮行星
Now, Stern argues that a dwarf planet is a kind of planet.
现在 Stern争辩说 一个矮行星也算一种行星
Just like how – The bonsai tree is still a tree.
就比如 盆栽也是树
And a Chihuahua is still a dog.
吉娃娃也是狗
– [Narrator] But other experts, like Montmerle,
但是其他专家们 比如Montmerle
prefer to think of dwarf planets as their own class.
更倾向于矮行星自成一派
So where does that leave us?
所以说这告诉我们什么呢
Well, in the grand scheme of things,
按照事物的大规律来说
it doesn’t really matter what Pluto’s official designation is.
冥王星的官方分类是什么 并不那么重要
– If people don’t like it, they don’t use it, period.
如果人们不喜欢这个名称 他们不用它就完事了
– [Narrator] Which is exactly what planetary scientists do.
而行星科学家就是这么做的
– So everyone’s using the planetary scientist’s
所以每个人在有文献的科学文学作品中
definition in the written, refereed scientific literature.
都使用了行星科学家的术语
And using it at the podium in giving scientific presentations.
在讲台上进行科学演讲时也用
That’s the kind of consensus that’s very powerful in science.
这是在科学界中的一种强烈共识
– [Narrator] So maybe Pluto isn’t a planet
所以 冥王星也许不是行星
the same way that Earth and Jupiter are planets.
像地球与木星那种行星
But that doesn’t mean we should ignore it.
可并不代表我们就要无视它
Besides, there’s more to this dwarf planet
再说了 这个矮行星
than meets the eye.
没有看上去这样简单
The New Horizons mission has found evidence
“新视野号”已经找到了这个星球上有
of ice volcanoes, hidden oceans.
冰火山 隐藏的海洋的证据
– There are evidence for icefalls and floes and glaciers.
还有冰崩 絮凝体 冰川的证据
Just tremendous stuff.
就是一些惊人的东西
– [Narrator] And that’s true, no matter what you call it.
不论你怎么称呼它 这些东西都在那里
