22 hours… and while I know there's a bit of rock in the way, that's really going the

22個小時... 雖然我知道有一點岩石在路上，但那真的是要去的。

long way round.

繞遠路。

So what if we did dig a hole all the way through the earth, through the center, and jumped

那如果我們真的挖了一個洞，從地心穿過，然後跳下去呢？

in?

在?

Well, Michael, you probably would't make it very far - that's because of the Coriolis

邁克爾 你可能走不了多遠 那是因為科里奧利的關係

effect (which is why a ball curves weirdly when you toss it while riding a merry go round

曲線效應

and why hurricanes always spin counterclockwise in the northern hemisphere). At the equator,

以及為什麼颶風在北半球總是逆時針旋轉）。)在赤道上。

the earth (and you on it) is rotating eastwards at 1670 km/hr. As you go deeper, the bits

地球（和你在地球上）正以1670公里/小時的速度向東旋轉。隨著你的深入，位

of earth around you are still spinning around once per day, but they don't have as far to

你周圍的地球仍在旋轉周圍每天一次，但他們不';遠到

travel so they're going at slower and slower speeds. If you jumped into a vertical shaft,

旅行，所以他們'的速度越來越慢。如果你跳進一個豎井。

you'd soon be traveling east faster than the rock around you so that after falling only

你'很快就會向東行駛，速度比周圍的岩石更快，所以在落下後只有

a few kilometers, you'd crash into the eastern wall. It might not be a disaster, but some

幾公里，你'會撞上東牆。這可能不是一場災難，但有些

miners near Lake Superior tried to test this by dropping cannon balls down a mile-long

蘇必利爾湖附近的礦工試圖通過向一英里長的湖中投擲炮彈來測試這一點。

shaft - and the balls never reached the bottom.

OK, so what if the tunnel went from pole to pole, so the Coriolis effect didn't apply,

好吧，那如果隧道從極點到極點，所以科里奧利效應不適用呢。

and let's also assume that there's no air resistance, or friction

並且讓我們也假設沒有空氣阻力，或者摩擦力。

Ok. Since the earth's mass is more concentrated close to the middle, gravity would pull you

好吧，由於地球的品質更集中在靠近中間的地方。由於地球的品質更集中在靠近中間的地方，引力會把你拉到這裡來

down with roughly the same amount of force for the first 3000 km, or halfway to the center

在前3000公里，或者說到中心點的一半，以大致相同的力氣下降。

of the earth - this familiar, constant force would accelerate you until you were falling

這股熟悉的、持續的力量會加速你的速度，直到你墜落下去

8km every second, and the trip halfway to the middle of the earth would only take 13

每秒鐘8公里，而到地球中部的半程只需要13。

minutes. Soon after, you'd reach the earth's outer core, and this is the point in your

分鐘。不久之後，你'就會到達地球的外核，這就是你的'中的一點。

journey where the pull of gravity would be strongest - but only slightly stronger than

在重力最強的地方旅行--但只是略微強過

the force we're used to on the surface.

我們在表面上習慣的力量。

As you continued to fall closer to the center, so much of the earth's mass would now be above

當你繼續向中心墜落時，地球的許多品質現在將在上方的'。

you that it would begin to seriously cancel out the attraction of the mass below, and

它將開始嚴重抵消下面的品質的吸引力，並。

the pull would weaken until you reached the center. Here, you'd experience no gravitational

拉力會減弱，直到你到達中心。在這裡，你將會體驗到沒有引力。

pull at all - or rather, the earth would be pulling on you the same amount in all directions,

拉力--或者說，地球在各個方向上對你的拉力都會是一樣的。

so you could float freely around with no sense of "up" or "down". Except, remember, that

所以你可以自由地飄來飄去，沒有"上"或"下"的感覺。除了，記住，那

you'd be speeding past at 22,000 miles per hour, or 6 miles a second.

你'會以每小時22000英里的速度飛馳而過，也就是每秒6英里。

Once you passed the center, the whole process would reverse and you'd gradually slow, pulled

一旦你通過了中心，整個過程就會反過來，你'會逐漸慢下來，拉著

down (or is it up?) weakly at first and then more strongly, until when you got to the other

先弱後強，直到你到了另一

side, you'd stop moving and could step out on the surface, a mere 37 minutes, or one

一邊，你會停止移動，並可以走出水面，僅37分鐘，或一個。

dryer cycle, later.

烘乾機週期，以後。

Of course, the deepest we've ever been able to dig is the Kola Superdeep borehole in Russia.

當然，我們能夠挖到的最深的是俄羅斯的科拉超深孔。

But it only went down 12km, which is only two thirds the length of Manhattan. They had

但它只下去了12公里，這只是曼哈頓的三分之二長度。他們有

to stop because it got too hot: 180°C. And this is sort of the problem with digging a

因為太熱而停止：180℃。這也是挖地道的問題所在。

hole through earth - earth is hot, and molten in the middle. You can't just dig a hole through

洞穿大地--大地是熱的，中間是熔化的。你不能只是挖一個洞，通過

it with shovels. But here's a question: wasn't the middle of earth wasn't all "liquidy",

它與鏟子。但這裡有一個問題：地球中部是不是不都是"液態"。

what if earth was hollow, but weighed the same?

如果地球是空心的，但重量相同呢？

Well, with its entire mass concentrated in a thin shell right under our feet, the earth

它的全部品質都集中在我們腳下的一個薄殼裡，地球上的人都是這樣的人

wouldn't have a magnetic field any more, because that comes from the molten iron core. So we'd

不會再有磁場了，因為那是來自於熔融的鐵芯的。所以我們

be totally vulnerable to radiation from the solar wind and storms, and this means we'd

是完全脆弱的輻射從太陽風和風暴，這意味著我們'd;。

see the aurora EVERYWHERE. Look! The NorthernSouthernEastern lights!

看到極光無處不在。看！北方-南方-東方的光！

And if you jumped inside the hollow earth to escape the solar storm? Well, gravity from

如果你為了躲避太陽風暴而跳進空心地球呢？那麼，重力從

the different parts of the spherical earth-shell would perfectly cancel out and you'd float

球形地球殼的不同部分將完美地抵消和你'd漂浮。

freely about inside as if the earth weren't there at all! Of course, you'd better bring

在裡面自由活動，好像地球根本不存在一樣!當然，你最好帶著

a space suit, because there's not nearly enough air ON earth to fill up the entire INSIDE

因為地球上沒有足夠的空氣來填充整個內部。

of earth. But what if the entire inside of the hollow earth were covered with mirrors?

的地球。但如果整個空心地球的內部都佈滿了鏡子呢？

Henry, that's ridiculous… for now

亨利，這太荒唐了... ...暫時如此

Ok, so back outside of the earth, we wouldn't really notice much difference from a gravitational

好吧，所以回到地球之外，我們不會真正注意到很多差異從引力

perspective - falling things would still accelerate at 9.8 m/s^2, a baseball would follow the

掉下來的東西仍然會以9.8米/秒^2的速度加速，一個棒球也會跟著加速。

same trajectory, and the moon would follow the same orbit around the earth.

同樣的軌跡，月球也會遵循同樣的繞地軌道。

Hey Henry, let's go to outer space, right now. Bring your gun - this'll all make sense

嘿，亨利，讓我們去外太空，現在。帶上你的槍 這一切都會變得有意義的

later. C'mon.

後來。C'mon。

Oh, and you're coming too. Click this annotation to head over to my channel, Vsauce, to see

哦，你'也來了。點擊這個註釋，可以到我的頻道Vsauce去看。

the rest of our adventures. I'll see you over there.

剩下的我們的冒險。我在那邊等你。