The best way to explore a new world is to land on it.
探索一个新世界最好的方式就是走进它里面，
That's why humans have sent spacecraft to the Moon, Venus, Mars, Saturn's moon Titan, and more.
这就是为什么我们会发射航空探测器到月球、金星、火星、土卫六等上头。
But there are a few places in the solar system we will never understand as well as we'd like.
但是太阳系有几个地方我们永远不会理解，也不会像我们想的那样。
One of them is Jupiter.
其中之一便是木星。
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.
木星主要由氢气和氦气组成，所以试图着陆它就像试图降落在地球上的云层上。
There's no outer crust to break your fall on Jupiter, just an endless stretch of atmosphere.
木星上没有外部地壳作为着陆点，有的只是无尽的大气。
The big question then is, could you fall through one end
of Jupiter and out the other?
随之而来最大的问题是，你能从木星的一端掉到另一端吗?
Turns out, you wouldn't even make it halfway.
事实是，你连一半都到不了，
First thing's first, Jupiter's atmosphere has no oxygen, so make sure you bring plenty with you to breathe.
首先，木星的大气层没有氧气，所以一定要带上足量的氧气可供呼吸。
The next problem is the scorching temperatures, so pack an air conditioner.
下一个问题是炎热的天气，所以你要打包带上个空调。
Now you're ready for a journey of epic proportions.
现在你已经可以准备踏上史诗般的旅程了。
For scale, here's how many Earths you could stack from Jupiter's center.
就规模而言，这是你能从木星的中心堆叠出多少个地球。
As you enter the top of the atmosphere,you're traveling at 110,000 miles-per-hour under the pull of Jupiter's gravity.
随着你进入木星大气层，在木星的重力作用下，你的速度大约在11万英里每小时
But brace yourself.
但振作起来！
You'll quickly hit the denser atmosphere below, which will hit you like a wall.
你很快就会碰到下面的密集的大气层，它会像一堵墙一样等着你怼。
It won't be enough to stop you, though.
尽管这样都不足以使你停下来，
After about three minutes, you'll reach the cloud tops 155 miles down.
大概3分钟之后吧你将到达155英里以下的云层。
Here, you'll experience the full brunt of Jupiter's rotation.
在这里，你将经历木星自转的全部冲击。
Jupiter is actually the fastest rotating planet in our solar system.
要知道，在太阳系统，木星是自转速度最快的。
One day lasts about nine-and-a-half Earth hours.
木星上的一天大约是地球上的9.5小时
This creates powerful winds that can whip around the planet at more than 300 miles-per-hour.
这就产生了一股强大的风，能以每小时300英里的速度绕着木星旋转。
About 75 miles below the clouds, you reach the limit of human exploration.
在离云层大约75英里的地方，你到达了人类探索的极限。
Galileo probe made it this far when it dove into Jupiter's atmosphere in 1995.
数据来自，1995年伽利略号探测器，就探测到这里。
It only lasted 58 minutes before losing contact and was eventually destroyed by the crushing pressure.
它只跟总部持续了58分钟便失去了联系，最终被极强的的压力摧毁。
Down here, the pressure is nearly 100 times what it is on Earth's surface and you won't be able to see anything,
在这里，压力几乎是地球表面的100倍，你看不到任何东西，
so you'll have to rely on instruments to explore your surroundings.
所以你必须依靠仪器来探索你周围的环境。
By 430 miles down, the pressure is 1,150times higher.
在430英里的高空，压强是地球的1150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.
当然如果你有一搜像Trieste样的宇宙飞船你也可以在里头活下来，至于Triester是目前地球上最深潜探测器。
Any deeper and the pressure and the temperature will be too great for the spacecraft to endure.
任何更深、更大的压力和温度都将使宇宙飞船难以承受。
However, let's say that you could find a way to descend even further.
但是，假设你可以找到一种进一步下降的方法。
You will uncover some of Jupiter's grandest mysteries.
你将揭开木星的一些最神秘的秘密。
But sadly, you'll have no way to tell anyone.
但是，悲剧的是，你没有途径告诉任何人。
Jupiter's deep atmosphere absorbs radio waves, so you'd be shut off from the outside world, unable to communicate.
木星的大气阻断了微波通讯。你与外界是一种隔离的状态无法通讯。
Once you've reached 2,500 miles down, the temperature is 6,100 degrees Fahrenheit.
一旦达到2500英里，温度就是6100华氏度。
That's hot enough to melt tungsten, the metal with the highest melting point in the universe.
这个温度，足以融掉钨，没错就是目前发现熔点最高的材料。
At this point, you will have been falling for at least 12 hours and you won't even be halfway through.
此时，你至少已经下降了12个小时，不过这甚至连一半都没到。
At 13,000 miles down, you'll reachJupiter's innermost layer.
当你下降到13000英里时，你将到达木星的最里层了。
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.
这里的压力是你站在地球表面的200万倍了，此处的温度，已经高于太阳表面了。
These conditions are so extreme that they change the chemistry of hydrogen around you.
这些极端条件，甚至会改变，你周围氢的化学性质。
Hydrogen molecules are forced so close together that their electrons break loose, forming an unusual substance called metallic hydrogen.
氢分子被迫如此紧密地结合在一起，以至于它们的电子逸散，形成一种叫做金属氢的不寻常物质。
Metallic hydrogen is highly reflective, so if you tried using lights to see down there, it would be impossible, and it's as dense as a rock.
金属氢是高度反射性的，所以如果你试着用灯光去看，那是不可能的，它就像岩石一样致密。
So as you travel deeper, the buoyancy force from the metallic hydrogen counteracts gravity's downward pull.
所以当你往深处移动时，金属氢的浮力会抵消重力的向下拉动作用。
Eventually, that buoyancy will shoot you back up until gravity pulls you right back down, sort of like a yo-yo, 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.
最终，这种浮力会把你推回去，直到引力把你拉回，有点像溜溜球，当这两种力量相等时，你会在木星的中部自由漂浮，无法上下移动，也无法逃脱。
Suffice it to say, trying to land on Jupiter is a bad idea.
我只想说，试图在木星上降落是个坏主意。
We may never see what's beneath those majestic clouds.
我们可能永远也看不到那些宏伟的云彩下面有什么。
But we can still study and admire this mysterious planet from afar.
但我们仍然可以在遥远的地方学习和欣赏这个神秘的星球。
,
