sent us our closest view of Saturn

給我們送來了土星的近景

as it dove into the planet's stormy atmosphere.

當它潛入地球的風暴大氣層時。

And the results were stunning.

而結果是驚人的。

But what would it be like

但那會是什麼樣子呢？

if humans made the journey in person?

如果人類親身前往？

At its closest,

在最接近。

Saturn is 1.2 billion kilometers away from Earth.

土星距離地球12億公里。

So with today's spacecraft technology,

所以以今天的航天技術。

you'll need about eight years to make the trip.

你需要8年的時間來完成這次旅行。

Finally, you arrive and get your first glimpse

終於，你到了，你第一次看到了

of Saturn with your own eyes.

親眼目睹土星的風采

It's an enormous planet,

這是一個巨大的星球。

the second largest in the solar system.

太陽系中第二大。

In fact, over 760 Earths can fit inside.

事實上，裡面可以容納760多個地球。

But hold up.

但是等一下

We can't visit Saturn and skip over

我們不能只去土星而不去土星

the best part, its iconic rings.

最棒的是，它的標誌性戒指。

Saturn's rings are almost as wide

土星環的寬度幾乎與地球一樣大

as the distance between the Earth and the moon,

作為地球和月球之間的距離。

so at first glance, they seem like

乍一看，他們好像

an easy place to land and explore on foot.

一個方便的落腳點和徒步探索的地方。

Except there's one problem.

除了有一個問題。

While they look like giant discs,

雖然它們看起來像巨大的圓盤。

they're not a solid track at all.

他們不是一個堅實的軌道在所有。

Instead, they're made of millions of chunks of ice,

相反，它們是由數百萬塊冰塊組成的。

some as tiny as dust particles,

有的細小如塵粒。

others as large as buses.

其他如公車一樣大。

But if you were able to hike

但如果你能徒步

on one of Saturn's outermost rings,

在土星最外層的一個環上。

you'll walk about 12 million kilometers

你要走1200萬公里

to make it around the longest one.

以使其在最長的一個周圍。

That's about 15 round trips from the Earth to the moon.

從地球到月球大約15次往返。

Along the way, you'll come across tiny moons

一路走來，你會遇到小月亮

and spokes of dust levitating above the surface.

和懸浮在地表之上的塵埃輻條。

Now, you might notice that streams of tiny ice particles

現在，你可能會注意到細小的冰粒的流向

are also flying off the rings, heading towards Saturn.

也正從環上飛出，向土星飛去。

That's ring rain.

那是環雨。

It turns out, Saturn's magnetic fields

原來，土星的磁場

are slowly but surely draining away the rings,

正在慢慢地但肯定地流走環。

so we're lucky to visit the rings now,

所以我們現在很幸運能去看戒指。

because every 30 minutes, they lose enough water

因為每隔30分鐘，它們就會失去足夠的水分

to fill an Olympic-sized swimming pool,

以填滿一個奧運會規模的游泳池。

and if we arrived 300 million years in the future,

而如果我們在未來三億年後到達。

we'd miss them entirely.

我們會完全錯過他們。

Now, let's climb back aboard

現在，讓我們回到船上

and visit the planet itself,

並參觀地球本身。

282,000 kilometers away.

28.2萬公里外。

As we reach the north pole,

當我們到達北極時。

we'll notice a slight problem with our plan

兵來將擋，水來土掩

to land on the surface below.

落在下面的地面上。

There is no surface below.

下面沒有表面。

Saturn's made almost entirely

土星幾乎完全由

of hydrogen and helium gas,

氫氣和氦氣的。

which is why it's called a gas giant.

這就是為什麼它被稱為氣體巨人。

4,000 kilometers above the surface,

離地面4000公里。

we hit Saturn's upper atmosphere.

我們撞上了土星的上層大氣

As we plummet through the north pole,

當我們跌落北極的時候。

we'll be treated to the sight of a magnificent aurora,

我們將看到壯觀的極光。

like the ones we see in Alaska.

就像我們在阿拉斯加看到的那些。

It turns out, Saturn's magnetic field

原來，土星的磁場

generates huge electrical currents,

產生巨大的電流。

which heat up the atmosphere at the poles.

使兩極的大氣加熱。

Unfortunately, the electrical activity

不幸的是，電活動

within this aurora can disrupt

在這極光中，可以擾亂

our ship's electronics and navigation system,

我們船上的電子和導航系統。

so best marvel at a distance.

所以最好在遠處驚歎。

Next, we'll hit the troposphere,

接下來，我們要去對流層。

the part of the atmosphere where weather happens.

大氣層中發生天氣的部分。

So watch out, powerful winds may slam into us

所以你要小心，強風可能會撞到我們的身上

at nearly 400 meters per second.

以每秒近400米的速度。

That's over three times faster

那是三倍以上的速度

than the strongest hurricanes on Earth.

比地球上最強的颶風。

All around us, thick yellow clouds

在我們周圍，厚厚的黃雲

give the planet its color.

給這個星球以顏色。

These are filled with ammonia crystals.

這些都是充滿了氨氣的晶體。

If you take a sniff, you might be able

如果你聞一聞，你可能會發現。

to smell that distinctive scent,

來聞到那獨特的香味。

but you should probably keep the window closed.

但你可能應該保持窗口關閉。

Ammonia is very irritating

氨氣是非常刺激的

and could wreak havoc on your respiratory system.

並可能對你的呼吸系統造成破壞。

Plus, it's freezing out here,

另外，這裡太冷了。

reaching as low as minus 250 degrees Celsius,

低至零下250攝氏度。

much colder than the East Antarctic Plateau,

比南極東高原冷得多。

the coldest place on Earth.

地球上最冷的地方。

So let's head down where it's a bit warmer.

所以，讓我們往下走，那裡更暖和一些。

Down here, at a depth of 300 kilometers,

在這下面，在300公里的深處。

we reach a layer of water,

我們到達一層水。

which is a balmy 0 degrees Celsius.

這是一個溫暖的0攝氏度。

Now, the deeper we plunge,

現在，我們越陷越深。

the higher the pressure is around us.

我們周圍的壓力就越大。

And in this next layer,

而在這下一層。

the pressure is so high,

壓力是如此之大。

it forces those liquid water molecules together,

它迫使這些液態水分子聚集在一起。

creating solid ice.

形成固態冰。

That ice mixes in with surrounding gasses,

這些冰與周圍的氣體混合在一起。

so get ready to fight through a flurry of hail.

所以，準備好通過一連串的冰雹戰鬥。

Hopefully, the ice won't shred our ship to pieces,

但願冰層不會把我們的船撕成碎片。

but if we make it through, get ready to go for a swim.

但如果我們能通過， 準備去游泳。

Because 1,000 kilometers into the interior,

因為進入內地1000公里。

the pressure is so high,

壓力是如此之大。

it forces hydrogen molecules together into a liquid,

它迫使氫分子聚集成液體。

which doesn't bode well for us,

這並不預示著我們的好。

since even the sturdiest submarine

堅船利炮

would be crushed in these conditions.

在這種情況下會被壓壞。

And if we somehow survive to reach the next layer,

如果我們以某種方式生存下來，到達下一層。

we'll hit yet another obstacle.

我們會遇到另一個障礙。

A layer of liquid metallic hydrogen.

一層液態金屬氫。

The problem here is that this metal can conduct electricity,

這裡的問題是，這種金屬可以導電。

so even if our navigation equipment and electronics

所以即使我們的導航設備和電子設備

escape the aurora upstairs,

逃離樓上的極光。

it's probably down for the count now.

它可能是下來的計數現在。

But if we could survive here,

但如果我們能在這裡生存下去。

our final stop might uncover a mystery

終點站可能會揭開謎底

in the deepest depths of Saturn.

在土星的最深處。

You see, scientists suspect Saturn has a core

科學家們懷疑土星有一個內核

made of iron and nickel,

由鐵和鎳製成。

but they're not sure if it's liquid,

但他們不確定它是否是液體。

like the previous layer, or solid, like Earth's core.

像前一層，或者像地核一樣的固體。

So maybe we'll be the lucky ones

也許我們會是幸運兒

to find out once and for all.

來一勞永逸地發現。

Though, it's over 83,000 degrees Celsius in here,

雖然，這裡的溫度超過83000攝氏度。

hotter than the surface of the sun

比太陽還熱

and hot enough to dissolve our spacecraft

並熱到足以溶解我們的航天器

with us inside!

和我們一起進去！

Hm.

Hm.

Maybe we should leave the Saturn exploration

也許我們應該離開土星探索

to unmanned probes after all.

到無人探測器，畢竟。