That's why humans have sent spacecrafts to the Moon, Venus, Mars, Saturn's moon Titan, and more.

這也是人類將太空船送到月球、金星、火星，以及土衛六泰坦等星球的原因。

But there are a few places in the solar system we will never understand as well as we'd like.

但太陽系中有些地方我們永遠無法如期望般地了解。

One of them is Jupiter.

其中一個就是木星。

Jupiter is made of mostly hydrogen and helium gas, so trying to land on it would be like trying to land on a cloud here on Earth.

木星主要是由氫氣和氦氣組成，所以嘗試登陸木星就像嘗試登上地球上的一片雲一樣。

There's no outer crust to break your fall on Jupiter, just an endless stretch of atmosphere.

木星沒有堅硬的外殼可以防止你掉落，只有無限延伸的大氣。

The big question then is: Could you fall through one end of Jupiter and out the other?

那麼重大的問題是：你可能從木星的某一端「跌」到另一端嗎？

Turns out, you wouldn't even make it halfway.

結果發現，你甚至連一半都到不了。

First things first, Jupiter's atmosphere has no oxygen, so make sure you bring plenty with you to breathe.

首先最重要的是，木星的大氣中沒有氧氣，所以記得要帶上足夠的量供你呼吸用。

The next problem is the scorching temperatures, so pack an air conditioner.

下一個問題是灼熱的溫度，所以記得帶上冷氣。

Now, you're ready for a journey of epic proportions.

現在你就準備好來一段壯麗的偉大旅程了。

For scale, here's how many Earths you could stack from Jupiter's center.

讓你當比例尺參考，可以看到從木星中心需要幾個地球來堆疊。

As you enter the top of the atmosphere, you're traveling at 110,000 miles per hour under the pull of Jupiter's gravity.

當你進入大氣頂端時，你會在木星重力拉扯下，以每小時十一萬英里的速度下墜。

But brace yourself.

但請做好準備。

You'll quickly hit the denser atmosphere below, which will hit you like a wall.

你很快就會抵達下方密度較高的大氣層，會讓你像是撞到牆一般。

It won't be enough to stop you, though.

但這阻止不了你下墜。

After about 3 minutes, you'll reach the cloud tops 155 miles down.

約莫 3 分鐘後，你將到達其下 155 英里的雲頂。

Here, you'll experience the full brunt of Jupiter's rotation.

你會在這裡充分感受到木星自轉的全部衝力。

Jupiter is actually the fastest rotating planet in our solar system.

木星其實是我們太陽系中自轉速度最快的行星。

One day lasts about 9 and a half Earth hours.

木星的一天的時間僅等同於地球的 9.5 小時。

This creates powerful winds that can whip around the planet at more than 300 miles per hour.

這會生產出每小時以逾 300 英里的強風繞著木星轉。

About 75 miles below the clouds, you reach the limit of human exploration.

雲層下方約 75 英里處，你就會達到人類探索的極限位置。

Galileo probe made it this far when it dove into Jupiter's atmosphere in 1995.

伽利略號探測器在 1995 年潛入木星大氣層時，達成了這個距離。

It only lasted 58 minutes before losing contact and was eventually destroyed by the crushing pressure.

它在失去通訊前僅維持了 58 分鐘，最終遭到巨大的壓力摧毀。

Down here, the pressure is nearly 100 times what it is on Earth's surface, and you won't be able to see anything,

在這個深度，壓力幾乎是地球表面的 100 倍，而且還看不到任何東西，

so you'll have to rely on instruments to explore your surroundings.

因此你必須依賴儀器來探索周圍。

By 430 miles down, the pressure is 1,150 times higher.

到了 430 英里深處，壓力便是 1,150 倍。

You might be able to survive down here if you were in a spacecraft built like the Trieste submarine, the deepest-diving submarine on Earth.

如果你在一艘像特里亞斯號（全世界潛水最深的潛水艇）的太空船上，那你就有可能在這裡倖存。

Any deeper and the pressure and the temperature will be too great for the spacecraft to endure.

稍微再深一點，其壓力及溫度之高都會讓太空船無法承受。

However, let's say that you could find a way to descend even further.

不過，我們假設你可以找到下降到更深處的方法。

You will uncover some of Jupiter's grandest mysteries.

你會揭開木星最偉大的奧秘。

But sadly, you'll have no way to tell anyone.

但遺憾的是，你沒有任何可以告訴其他人的管道。

Jupiter's deep atmosphere absorbs radio waves, so you'd be shut off from the outside world, unable to communicate.

木星深厚的大氣會吸收無線電波，因此你與外界的聯繫會被阻斷，無法進行通訊。

Once you've reached 2,500 miles down, the temperature is 6,100 degrees Fahrenheit.

一旦你下降到 2,500 英里處，那裡的溫度是華氏 6,100 度（約攝氏 3,371 度）。

That's hot enough to melt tungsten, the metal with the highest melting point in the universe.

這溫度足以融化鎢，宇宙中熔點最高的金屬。

At this point, you will have been falling for at least 12 hours, and you won't even be halfway through.

在此時，你將已經持續下降 12 小時，但卻連木星的一半都還沒到。

At 13,000 miles down, you'll reach Jupiter's innermost layer.

下降到 13,000 英里時，你將抵達木星的最深層。

Here, the pressure is two million times stronger than that of Earth's surface, and the temperature is hotter than the surface of the Sun.

這裡的壓力比地球表面高兩百萬倍，而溫度比太陽表面還高。

These conditions are so extreme that they change the chemistry of hydrogen around you.

這裡的環境極端到足以改變周圍氫氣的化學性質。

Hydrogen molecules are forced so close together that their electrons break loose, forming an unusual substance called metallic hydrogen.

氫分子受到強大壓力緊壓，使得電子掙脫，形成一種叫「金屬氫」的獨特物質。

Metallic hydrogen is highly reflective.

金屬氫具有高反射性。

So if you tried using lights to see down there, it would be impossible, and it's as dense as a rock.

因此如果你想用在那裡用燈光輔佐視力，是完全不可能的，而且它的密度和岩石一樣高。

So, as you travel deeper, the buoyancy force from the metallic hydrogen counteracts gravity's downward pull.

因此，當你下降到更深處時，金屬氫的浮力會抵消向下沉的重力。

Eventually, that buoyancy will shoot you back up until gravity pulls you right back down, sort of like a yo-yo.

最後，浮力會將你彈回去，直到重力把你往下拉，讓你變得有點像溜溜球。

And when those two forces equal, you'll be left free-floating in mid-Jupiter, unable to move up or down, and no way of escape.

而當這兩種力達到平衡時，你將滯留在木星中間自由浮動，無法往上或向下，也無法掙脫。

Suffice it to say, trying to land on Jupiter is a bad idea.

不用多說，嘗試登陸木星是個爛主意。

We may never see what's beneath those majestic clouds.

我們可能永遠都無法看到那些宏偉雲層下的景觀。

But we can still study and admire this mysterious planet from afar.

但我們仍可以從遠端研究和欣賞這神秘的行星。