I can fix that.

我可以搞定這問題。

Hey guys, Amy here to talk space on DNews.

嘿，大家好，Amy 在 DNews 來談談宇宙。

There has been a lot of talk recently about dwarf planets vs. “regular” planets, comets,

最近有許多關於矮行星 vs.「常規」行星、彗星

asteroids… not to mention some questions what what exactly a natural satellite is.

小行星的討論......更不用說某些問題，關於天然衛星究竟是什麼。

Well, let's break down what exactly is kicking around in our Solar System.

那麼，我們來分析一下究竟有什麼東西，在太陽系中在到處遊走。

At the centre is our Sun, which is a star.

太陽系中心是我們的太陽，是一顆恆星。

A star is a luminous ball of gas, mostly hydrogen and helium, that is held together by its own gravity

恆星是一種發光的氣體球，主要為氫氣和氦氣，通過自身重力固定在一起。

Nuclear fusion in its core produces photons, the light particles we see, as well as heat and trace amounts of other heavy elements.

其中心的核融合產生出光子，我們看到的光粒子，以及熱量和其他重元素的痕量。

But not all stars are the same.

但不是所有恆星都一樣。

Stars can be different colours depending on their temperature, hotter stars looking slightly

根據溫度的不同，恆星可以是不同顏色，較熱的恆星看起來略為偏藍，

bluer while cooler stars look slightly more red.

而較冷的恆星看起來略為偏紅。

And stars are typically different sizes, the cooler stars being smaller.

而恆星一般來說大小會不同，較冷的恆星就會偏小。

As stars evolve and age, depending on their mass, they expand and eventually puff up as

隨著恆星的進化和老化，取決於它們的質量，它們會膨脹，最後像紅巨星一樣膨脹

red giants and rip themselves to shreds (that's what happens to stars about the mass of our Sun)

並將自己撕成碎片 (這就是恆星對太陽質量的影響)，

and turn into a white dwarf or, if they are really massive, they explode as supernovas

然後變成矮行星，或者說，如果它們真的很大，它們會在變成

before turning into neutron stars or black holes.

中子星或黑洞前，爆炸成超新星。

Then there are brown dwarfs, which are sometimes called failed stars because they just aren't

接著是棕矮星，有時稱為失敗的恆星，因為它們不夠大，

big enough to start the fusion reaction that makes a star bright.

無法進行使恆星變亮的聚變反應。

Brown dwarfs also have planet-like qualities, making them a kind of bridge between stars and planets.

棕矮星也具行星般的特性，讓它們成為恆星和行星間的橋樑。

Orbiting all kinds of stars are the planets, but for a body to be classified as a planet

圍繞各種恆星運行的是行星，但對於歸類為行星的天體，

it has to meet three additional criteria laid out by the International Astronomical Union:

必須符合國際天文學聯合會制定的三個額外準則：

It has to be large enough to be round, it cannot be a satellite of another body,

它必須足夠大才能成圓形，它不能是另一個天體的衛星，

and it must have cleared its orbit of all nearby debris.

它必須清除附近軌道的所有碎片。

This all basically puts a minimum size limit on planets, but as long and they're big

這一切基本上對行星設置最小的尺寸限制，但是只要它們夠大，

enough planets can come in different types and sizes.

行星就可以有不同類型和大小。

Earth is a rocky, terrestrial planet, as are Mercury, Venus, and Mars.

地球是由多種岩石構成的類地行星，水星、金星及火星也一樣。

The outer planets Jupiter, Saturn, Uranus, and Neptune, are called gas giants, though those last two are sometimes called ice giants as well.

其他行星如木星、土星、天王星以及海王星，稱為氣態巨行星，但最後兩個有時也稱為冰巨行星。

When we talk about planets around other stars, we have slightly different descriptors.

我們談到其他恆星周圍的行星時，我們稍微有不同的描述。

There are super Earths, which aren't exactly what they sound like.

有超級地球這種星體，但絕不像他們的名字一樣。

These are planets more massive than Earth but still far less massive than Uranus or

它們的質量比地球還大，但仍然比天王星和海王星小很多，

Neptune, which are 15 and 17 times as massive as the Earth respectively.

天王星和海王星的質量分別是地球的 15 倍和 17 倍。

On the other end of the size spectrum are dwarf planets, planets that are too small

徑譜另一端的是矮行星，行星太小

to have cleared their orbital path of debris, like Ceres, the dwarf planet we've talked about before, in the asteroid belt.

而無法清除它們的軌道碎片，像是我們上次談到的穀神星，它在小行星帶。

Pluto is a dwarf planet as well, though in recognition of everyone's favourite little body,

冥王星也是一顆矮行星，為了表示大家都喜歡矮小的天體，

the IAU recently designated all dwarf planets that orbit beyond Neptune as plutoids.

IAU 近期將所有海王星外運行的矮行星，稱呼為類冥矮行星。

But regardless of size, type, or distance from its host star, any planet can have a moon.

但不論大小、類型，或是與主星的距離，任何行星都會有月球。

A moon is a natural satellite, a body that makes an orbit around a planet.

月球是一顆天然衛星，圍繞行星運行的天體。

Moons can have water like Europa, can have thick atmospheres like Titan, or be, for all

月球可以像歐羅巴一樣有水，可以像泰坦有濃厚的大氣層，或是

intents and purposes, a dead world like our own Moon.

在所有方面，像我們的月球一樣，是個死寂的世界。

As long as it's orbiting a planet, it's a moon.

只要它繞行星運行，它就是月球。

Of course, there are more subcategories and intricacies in individual bodies, but those are sort of the basics.

當然，在個別天體中，還有更多子範疇和複雜的細節，但這些是基本知識。

Does that clear things up?

這樣有清楚了嗎？

If you have any more questions on celestial bodies, let us know in the comments below or you can ask me on Twitter as @astVintageSpace.

如果你對天體有任何問題，就在下方留言告訴我們，或者上推特問我 @astVintageSpace。

And don't forget to subscribe for more DNews every day of the week.

為了看到 DNews 每天的內容，別忘了訂閱。