(单词翻译:单击)
Hey there! Welcome to Life Noggin.
大家好！这里是脑洞大开的生命奇想。
Right now you're probably watching this video from somewhere on Earth... that big, round beautiful planet you humans call home.
此刻你可能正在地球上的某个地方看这个视频……那个又大又圆的美丽星球，你们人类称之为家。
But how do you know the Earth is round? Your senses would tell you that it's flat.
但是你怎么知道地球是圆的？你的感官会告诉你它是平的。
After all, if you stand in a large field, it actually looks pretty flat.
毕竟，如果你站在一个大的场地里，它实际上看起来很平坦。
And if you walk through that field, it doesn't feel like you're going over a curve. Could it be that the Earth is actually flat?
如果你在这个场地上走一圈，你不会觉得在走一条曲线。难道地球其实是平的吗？
Well, let's try an experiment. Say you're standing in a field outside of Chicago.
我们来做个实验。假设你站在芝加哥郊外的田野里。
If the Earth is flat, you should be able to see southwest and see some of the tallest points in the United States, the Rocky Mountains.
如果地球是平的，你应该能往西南方看，看到美国最高的一些地方，也就是落基山脉。
But the thing is, you can't. That's because of the curvature of the Earth.
但问题是，你不能。那是地球的曲率造成的。
You'll notice a similar problem if you stand on a seashore and try to watch a boat sail away. After awhile, it will disappear from view.
如果你站在海边，试着看一艘船驶离，你会注意到一个类似的问题。过一段时间，它将从视野中消失。
And not only that, but the bottom of the boat will vanish before the top as it goes over what's called the horizon line — the place where the sky meets the Earth.
不仅如此，当船经过所谓的海天相交的地平线时，船底比顶部先消失。
For someone who is six feet tall, the horizon line is only three miles away.
对于一个六英尺高的人来说，地平线只有三英里远。
But the higher up you are, the farther you can see over the Earth's curve.
但是你爬得越高，你就能在地面这条曲线上看得越远。
This is why standing on a tall mountain might allow you to see over 100 miles while standing in a field will only let you see a short distance.
这就是为什么站在高山上可以看100多英里，而站在田野里只能看到很短的距离。
It also means that taller people can see slightly farther than shorter people.
这也意味着高个子的人比矮个子的人看得稍微远一点。
Good thing my animator can make me any height! See? I'm like one ant dude.
幸好我的动画师能让我长到任何高度！看到了吗？我就像一只蚁族。
The thing is, none of this is new information. We've known about the planet's curvature for over 2000 years.
问题是，这些都不是新的信息。我们2000多年前就已经知道地球的曲率了。
The Ancient Greeks figured out that the Earth is round based on several pieces of evidence, including their observations of ships going over the horizon line.
古希腊人发现地球是圆的，他们的几条证据包括他们对船只越过地平线时的观察。
The scientist Aristotle, writing in 350 BCE, noted that during an eclipse, the Earth makes a round shadow on the moon.
科学家亚里士多德在公元前350年写道，他注意到在月食期间，地球在月球上投下了一个圆形的影子。
He also realized that stars appear in different places depending on where you are standing.
他还意识到，所站的位置不同，看到的星星出现的位置也不同。
For example, he saw stars in Egypt that weren't visible farther north.
例如，他在埃及看到的星星，往北走远一点就看不到了。
Roughly 100 years later, humans got their first measurements of the Earth's curve from another Greek mathematician, Eratosthenes.
大约100年后，另一位希腊数学家埃拉托色尼对地球曲度进行了测量，这是人类对地球曲度的第一次测量。
He had heard of a city in southern Egypt where, at noon on the summer solstice, the sun was directly overhead and the buildings cast no shadows.
他听说，在埃及南部的一个城市，夏至的中午，太阳直射头顶，建筑物没有投影。
But at the same time in the northern city of Alexandria, the buildings did cast shadows... meaning the sun was at a different angle in the sky.
但与此同时，在北部城市亚历山大，建筑投下了阴影……这意味着太阳在天空的角度不同。
On the day of the solstice, Eratosthenes stuck a stick in the ground in Alexandria and measured the angle of its shadow.
夏至那天，埃拉托色尼在亚历山大城的地上插了一根棍子，测量了它影子的角度。
Using the distance between the two cities, he was able to calculate the curvature of the Earth!
利用两个城市之间的距离，他计算出了地球的曲率！
You could actually perform this same experiment if you have a friend living a few miles away.
如果你有朋友住在几英里外，你可以做同样的实验。
Or, if your friend is several hours west, you can get more proof that the Earth is round by calling them at sunset and asking how the sky looks.
或者，如果你的朋友住在西边几个时区之外，你可以在日落时给他们打电话，询问天空的样子，以证明地球是圆的。
It will still be daylight there because of the Earth's curve.
因为地球的曲度，那里仍然是白天。
And there's one more piece of clear evidence for the planet's shape — pictures taken from space.
还有一个清晰的证据可以证明这颗行星的形状——从太空拍摄的照片。
Maybe you're not on Earth after all and are actually watching this video from the space station… in which case, please leave a comment, because that's so cool.
也许你根本就不在地球上，而是在从空间站上看这个视频…如果是这样的话，请留下评论，因为那太酷了。
If that's true, you'll have a bird's-eye view of this giant blue and green globe. What a beautiful place to live.
如果这是真的，你可以鸟瞰这个巨大的蓝绿相间的地球。我们住在多么美丽的地方啊。
So what other myths about Earth do you want me to explore?
那么还有没有其他你们想让我探索的关于地球的错误看法吗？
Let me know in the comment section below.
请在下面的评论部分告诉我。
Do you love science? Do you love video games?
你喜欢科学吗？你喜欢电子游戏吗？
If so, you have to check out Play Noggin, which is an excellent combination of the two.
如果都喜欢的话，你必须去看看Play Noggin，它完美地结合了两者。
Julian recently explored the idea of mind control. Check it out!
朱利安最近探索了精神控制的概念。点击这里查看详情！
If the colander our protagonist puts on his head allows him to hack into the minds of his less intellectual friends, then in theory, he could exercise control over their actions.
如果我们的主角戴在头上的滤器，让他能侵入那些没他聪明的朋友的思想，那么理论上他就能控制他们的行为。
At a basic level, it doesn't sound too complicated. In order to control the activity in an area of the brain, you need to stimulate it with energies.
基本上，这听起来并不复杂。为了控制大脑某个区域的活动，你需要用能量来刺激它。
My name is Blocko. This has been Life Noggin. Don't forget to keep on thinking.
我是宝高，这里是脑洞大开的生命奇想。思考不要停。
