人类大历史（2013）

Big History S01E06

Part 3 March 29, 2021, 2:02 p.m.

And because gases in the atmosphere can carry electric charges...
就是静电所产生的一个星火
it is a simple spark of static electricity...
摧毁了兴登堡号♥
that' dooms the Hindenburg.
但是导致兴登堡号♥最终毁灭的大气
But the atmosphere that carries the Hindenburg's destruction...
也同样支撑着它
is also what supports it...
以及其他所有的飞行物
and everything else that flies.
正如同水提供了一个游泳的环境
Just as water provides an environment for swimming...
大气于地球就如同水但比水更薄
Earth is atmosphere, thinner than water. -.
它们拥有同样的特质
But with many of the same qualities...
给我们一些推压的力量
gives us something to push against...
所以我们可以飞行
so we can fly.
打个比方把一个太空面罩套在一只鸟的头上
Let's get a bird and give him a space suit just over his face...
然后把它扔进太空中
and put him in space.
它会像发了疯似得原地拍打翅膀
And he's gonna flap like crazy and go nowhere.
没有东西可以以我们所知道的方式在太空飞行
Things can't fly in space by flying as we know it.
为什么呢
Why is this?
因为飞行需要你有
Because flying requires you
挥动翅膀产生推力
to have wings that are pushing against something.
当你做一个俯卧撑
When you do a pushup,
你可以借用反方向力来支撑你
you're using the ground to lift yourself up.
当你飞行的时候你就用你的翅磅
When you're flying, you're using your wings...
推压气体来让你升空
to push against molecules to lift yourself up.
控制这无形海洋的力量是什么
And the force holding this invisible ocean in place?
就是重力
Gravity...
推动气体原子让它们围绕着我们的星球
pulling on the atoms of gas to keep them around the planet.
你尝试去
You're trying to strike this delicate balance...
打破用来支撑你的大气
between using the atmosphere to support you...
和你需要战胜的重力间的这种微妙的平衡
and to overcome the, sort of, pull of gravity.
地球恰到好处的重力
Earth has just the right amount of gravity...
以及恰到好处的大气浓度使得飞行成为了可能
just the right density of atmosphere to make flight possible.
飞行永恒的敌人
The eternal enemy of flight...
也恰好就是让飞行成为可能的东西
is also what makes flight on earth possible.
所以当我们反抗重力的时候
So we must rely on gravity
我们又不得不依赖它
while we defy it.
大历史揭示了我们的星球
Big history reveals that the planet...
是破解飞行密♥码♥的关键
is the Key to cracking the code of flight.
但飞行篇章仅仅是一个开始
But the story of flight is just the beginning.
大历史中还蕴藏着更大的谜团
There's a much bigger puzzle hidden in big history.
每集解锁一条线索
Each episode unlocks a clue.
任何常见的东西比如山
Everyday things like mountains...
银
silver...
还有电♥话♥
and cell phones...
都可能暗藏玄机
hold the key.
审视它们你就会解开这个大谜团
Watch them all, and you'll see this grand mystery revealed-
历史宇宙
the big history of time, of space...
以及我们自身
the big history of us.