Welcome to Life Noggin.

歡迎來到生命諾金。

You Earthlings are pretty attached to your sun, and for good reason.

你們地球人對太陽很有感情，這是有原因的。

It provides light and heat, drives photosynthesis that makes oxygen, and helps generate weather

它能提供光和熱，推動光合作用製造氧氣，並幫助產生天氣。

patterns.

模式。

Without it, you wouldn’t exist.

沒有它，你就不會存在。

But if the sun is so great, would it be better if there was more of it?

但是，如果太陽這麼大，是不是多一些就好了？

What if the sun has twice the mass it has now?

如果太陽的品質是現在的兩倍呢？

Too much of a good thing can be a bad thing, and in this case, it would so bad that no

太多的好東西可能是一件壞事，在這種情況下，它會如此糟糕，以至於不

one would survive.

一個會活下來。

But before I get to that, you have to understand why mass makes a difference.

但在我說這個之前，你得先明白為什麼品質會有差別。

As you probably know, the sun is a star, and stars come in a variety of masses.

你可能知道，太陽是一顆恆星，而恆星的品質有很多種。

Generally, a star with more mass — more matter packed into it — glows brighter and

一般來說，品質越大的恆星--裡面裝的物質越多--越發明亮，而且會有更多的能量。

hotter than one with less.

比少的人更熱。

The smallest stars can be less than 8 percent the mass of the sun and give off only .01

最小的恆星的品質可能不到太陽品質的8%，僅發出0.01

percent as much energy.

％的能量。

The largest stars can be a hundred times more massive than the sun and emit thousands of

最大的恆星可以比太陽大上百倍，併發出數千顆

times as much energy.

倍的能量。

Compared to these stars, the sun is actually a pretty normal mass.

與這些恆星相比，太陽的品質其實很正常。

But that doesn’t make its relationship to Earth any less special.

但這並不意味著它與地球的關係就不那麼特殊。

Many planets are either too close or too far away from their stars to support life.

許多行星要麼離恆星太近，要麼離恆星太遠，無法支持生命。

Earth is in what we call the Goldilocks Zone, or the habitable zone, where it’s just far

地球處於我們所說的金髮區，或者說是可居住區，在這裡，它只是遠遠地...

enough away from the sun to have the right temperature for life to exist.

離太陽足夠遠的地方才有合適的溫度讓生命存在。

And we’re not the only planet like this.

而且我們不是唯一一個這樣的星球。

Scientists believe there are billions of Earth-like planets in habitable zones across the Milky

科學家們認為，在銀河系的可居住區中，有數十億顆類地行星。

Way!

辦法！

In fact, in early 2017, NASA announced they’d found seven exoplanets 39 light years away

事實上，在2017年初，NASA宣佈他們發現了7顆39光年外的系外行星。

that might have water, and three of them are in their star’s habitable zone.

可能有水的，其中有三個在恆星的可居住區。

But all of them orbit their star closer than Mercury orbits the sun, so… why don’t

但它們的軌道都比水星繞太陽的軌道要近 所以...

they burn up?

他們燒起來了？

Well, distance is only part of the equation.

嗯，距離只是等式的一部分。

These planets orbit an ultra-cool, very small dwarf star only 8 percent as massive as the

這些行星圍繞著一顆超冷、極小的矮星運行，其品質僅有天鵝座的8%。

sun.

太陽。

It’s also half as cold as the sun and less than one-thousandth as bright.

它的溫度也只有太陽的一半，亮度也不到太陽的千分之一。

Being close to this star is the only way the planets could possibly capture enough light

只有靠近這顆恆星，行星才有可能捕捉到足夠的光。

and heat to support life.

和熱量來維持生命。

If they were farther away, they would be too cold for life to exist.

如果它們離得更遠，它們就會太冷，生命就不會存在。

So, back to your solar system.

所以，回到你的太陽能系統。

If the sun were twice as massive as it is now, Earth would fall out of the habitable

如果太陽的品質是現在的兩倍，地球就會掉出宜居的範圍。

zone… way out.

區... 出路。

First off, with more mass, the sun’s luminosity — the amount of energy and brightness it

首先，隨著品質的增加，太陽的光度--它的能量和亮度也會隨之增加。

gives off — would increase exponentially.

散發出的--會成倍增加。

To see what might happen to you, let’s look at Sirius A, the brightest star in your sky.

為了看看你會發生什麼，讓我們看看天狼星A，你天空中最亮的星星。

It’s just about twice as massive as the sun but more than 20 times as luminous.

它的體積大約是太陽的兩倍，但光度卻是太陽的20多倍。

It’s also several thousand degrees hotter — well over 9000 degrees celsius, compared

它的溫度也要高出幾千度--遠遠超過9000攝氏度，相比之下。

to 5500 degrees for the sun.

到5500度的太陽。

If the sun was that massive and Earth kept the same distance from it, you’d be toast,

如果太陽那麼大，而地球與它保持同樣的距離，你就會被烤焦。

maybe literally.

也許是字面上的意思。

Earth would not just get significantly hotter, but the oceans would boil away, leaving a

地球不僅會變得更熱，而且海洋會沸騰，留下一個

vapor cloud that would trap even more heat.

蒸汽雲，會捕捉更多的熱量。

Plus, if the sun doubled in mass, its gravitational pull would increase.

另外，如果太陽的品質增加一倍，它的引力就會增加。

This could change the Earth’s orbit and tidal patterns, possibly making tides stronger.

這可能會改變地球的軌道和潮汐模式，可能會使潮汐變得更強。

All of this would not be good for you Earthlings.

這一切對你們地球人來說都不是好事。

I think it’s probably better to appreciate the sun you have now.

我想，也許還是好好珍惜現在的陽光吧。

Want to know what would happen if the Earth doubled in size?

想知道如果地球體積擴大一倍會發生什麼嗎？

Check out this video.

看看這個視頻。

Do you think life exists on other planets in these habitable zones?

你認為在這些可居住區的其他星球上有生命存在嗎？

Let me know in the comment section below.

請在下面的評論區告訴我。