Well, it's a model of our solar system.

一個太陽系的模型。

Sun at the center and the eight planets that orbit it.

中心的太陽，和八個環繞它的行星。

Wait a second. What's this?

等一下，這顆是什麼？

Pluto?

冥王星？

What are you doing here, Pluto?

冥王星，你在這做什麼？

What?

什麼？

Well, don't look at me like that. What do you want me to do?

不要那樣看我，你要我怎麼做？

You're technically not a planet anymore; you're a dwarf planet.

技術上來說你已經不是行星了，你是一個矮行星。

But that doesn't mean you're not important.

但這不代表你不重要。

Oh, Pluto, your discovery was very important.

冥王星，你的發現十分重要。

And it led to us learning even more about our solar system.

讓我們更了解太陽系。

Yeah, that's right.

對，沒錯。

Let me explain, but let's go back a bit.

讓我解釋，但我們把時間往回拉一點。

It was the ancient Babylonians that first observed the planets in our solar system.

古巴比倫人首次觀測到太陽系的行星。

They noticed that while most stars stayed in the same position relative to each other, some of them would move around the sky.

他們發現大多數恆星會彼此保持相同的位置，但其中一些會在天空中移動。

They weren't stars at all; they were planets.

它們不是星星，而是行星。

In fact, the word "planet" comes from the Greek word "wanderer" because they... wandered through the sky.

其實「行星」這個詞是源自希臘語的「漫遊者」，因為它們會在天空中徘徊。

At first, we thought there were only five planets: Mercury, Venus, Mars, Jupiter, and Saturn.

在一開始，我們認為只有五顆行星：水星、金星、火星、木星和土星。

Then, in the 16th century, we realized that Earth was also a planet.

後來在 16 世紀，我們發現地球也是一個行星。

Yep! Mind blown.

對！吃驚吧。

It was Nicolaus Copernicus in 1543 that suggested the planets revolved around the sun.

尼古拉·哥白尼在 1543 年提出行星環繞太陽一說。

It took a few years to catch on, but eventually, people accepted the idea.

雖然花了幾年大眾才理解，但最後人們接受了這個想法。

About 200 or so years later, we discovered Uranus.

大概 200 多年後，我們發現天王星。

Hey! No jokes, please, Pluto.

嘿！冥王星，別亂開玩笑。

Cheeky.

放肆。

Like the other planets, you can see Uranus without a telescope.

就像其他行星，你不用望遠鏡就能看到天王星。

Because it's quite dim and moves very slowly, no one really noticed it, until 1781, when astronomer and composer Frederick William Herschel came along and discovered it.

因為它很昏暗，移動也很緩慢，所以沒有人注意到它。直到 1781 年，身兼天文學家和作曲家的威廉·赫雪爾才發現它。

Then, in 1846, astronomers noticed something weird happening to Uranus's orbit.

接著在 1846 年，天文學家們注意到天王星軌道發生一些奇怪的事情。

Turns out, it was because of the gravitational pull of Planet Eight, Neptune.

原來那是因為第八號行星——海王星的萬有引力。

And that brings us to Pluto.

這讓我們找到冥王星。

In 1930, American astronomer Clyde Tombaugh was checking out images he'd taken of the stars and realized one of those specks of light kept moving.

在 1930 年，美國天文學家克萊德·湯博在查看他拍攝的行星圖像時，發現其中一個光點一直在移動。

Pluto's discovery made headlines.

冥王星的發現成為新聞頭條。

Its name was actually suggested by an 11-year-old, who thought it would be cool to name it after the Roman god of the underworld, seeing as Pluto lives in such a cold and desolate part of the Solar System.

它的名字其實是由 11 歲小孩命名的，他覺得以羅馬冥界之神的名字來命名很酷，因為他注意到冥王星生活在太陽系寒冷和荒涼的地方。

Then, we spent the next few decades remembering the names of all nine planets in our solar system, until...

後來，我們在接下來的幾十年裡記住了太陽系中所有九顆行星的名字，直到……。

Yep, Pluto, my friend, you were downgraded to a dwarf planet.

沒錯，冥王星，我的朋友，你被降級成矮行星。

I mean, you are pretty small compared to the others.

你跟其他行星相比起來太小顆了。

Especially that one.

尤其是這顆。

And that one.

和這顆。

And that one.

那顆也是。

Well, all of them, really.

全部都比你大。

You're actually smaller than our moon.

你甚至比月亮還小。

And Australia.

也比澳洲小。

Yeah, you're pretty tiny.

你真的太微小了。

Plus, we've found a bunch of other objects in the Solar System that are much bigger than Pluto, but not quite big enough to be planets.

而且，我們發現太陽系中有許多天體都比冥王星大很多，但都還不足以成為行星。

In 2016, we sent this spacecraft to study Pluto, found out it had a bunch of moons, and, best of all, had a big old love heart on its surface.

在 2016 年，我們發射太空船去研究冥王星，並發現它有一堆衛星，最重要的是，它的表面上有一顆古老的愛心。

Awww!

哦！

So, to some of us, you'll always have a special place in our Solar System.

對某些人來說，你將永遠在我們的太陽系中佔有一個特殊的位置。

Just, uh, not this model because, you know, accuracy.

但因為準確性，所以不是在這個模型上。

Yeah.

沒錯。