Within the iron core, the rotating ball of molten iron generated a remarkable magnetic field.

得益于地球的铁质核心不断旋转对流逐渐产生了地磁场。

Astronomers have observed a distant planet with conditions so extreme that probably rains molten iron.

天文学家观测到一颗遥远的恒星，这颗恒星上的气候十分极端，雨水竟是铁水。

The Earth has a molten iron core that rotates quickly, turning it into a giant magnet.

地球有一个快速旋转的熔融铁核，把地球变成了一个巨大的磁体。

In others, they're just cool enough that iron condenses out of the atmosphere… which means it literally rains molten iron!

而另一些，它们的温度足够低，铁就会从大气中凝结出来… … 这就意味着它会像下雨降雨熔铁！

Some have the density of cotton candy, and others rain molten iron.

有的有棉花糖的密度，有的像雨滴的铁水。

Fortunately, the earth is protected from its radiation by a magnetic shield, a kind of force field generated by our molten iron core.

幸运的是, 地球由于磁屏障而免受辐射, 这是一种由我们的核心产生的磁场力屏障。

The old city walls have been recreated and throwing molten iron onto those ancient walls was where Mr. Xue's forefathers invented the art.

老城墙被复建起来了铁水就是被抛向这些老城墙正是薛先生的先祖创造了这项技艺。

And for reasons still unknown to scientists, the molten iron's motion must somehow change to reverse the magnetic field.

由于科学家尚不清楚的原因，铁水的运动必须以某种方式改变以反转磁场。

Creating a light show out of molten iron is a dangerous business, but Mr Xue has agreed to show me how it is done.

用热熔铁水打出光耀是项危险的行当，但薛先生同意为我展示这一技艺。

In Hebei's Nuanquan town, residents put on a spectacular " firework" show by throwing molten iron against a cold stone city wall to create sparks.

在河北暖泉镇，居民们上演了一场壮观的“烟花”表演，他们将熔化的铁水扔向冰冷的石头城墙，来产生火花。

But that fits with so much of its interior being molten iron: the bigger core may allow for a stronger field despite its slow spin.

尽管自转较慢，大一点的核会形成更强的磁场。

Well, the reason that the Earth even has a magnetic field has to do with the molten iron in the outer core.

好吧，地球甚至有磁场的原因都与外核中的铁水有关。

And the motion of that molten iron, along with some complicated physics, generates a magnetic field through something called the dynamo effect.

铁水的运动， 连同一些复杂的物理现象，通过一种叫做发电机效应的东西产生了磁场。

The molten iron has been cooking for about 45 minutes and it is looking pretty hot but, before we let any sparks fly, Mr Xue has to get into protective clothing.

铁水已经烧了大约45分钟了，看着也非常热了但在火花飞溅之前，薛先生需要穿上防护服。

And when you use a compass, you are in touch with the very center of our planet, where this kind of roiling ball of molten iron is spinning around and creating a magnetic field.

当你使用指南针时，你会接触到我们星球的中心，这种旋转的铁水球正在旋转并产生磁场。

The man who first suggested that so commonplace a substance as air, blown upon molten pig iron, would produce the intensest heat and destroy its impurities, made possible our steel railroads, our steel ships, and our steel cities.

第一个提出像空气这样普通的物质，吹在熔化的生铁上，会产生最强烈的热量并破坏其中的杂质的人，使我们的钢铁铁路、我们的钢船和我们的钢铁城市成为可能。