如果太阳消失一个月会发生什么？：英语精读讲义

This episode was sponsored by Google Science Fair.

本集视频由 Google Science Fair 赞助播出。

A near-perfect sphere of hot plasma with a core that's more than 15 million degrees Celsius,

一个由炽热等离子体构成、核心温度超过 1500 万摄氏度的近乎完美球体——

the sun is the most important source of energy for life on Earth.

太阳，是地球生命最重要的能量来源。

But what if it suddenly disappeared for a month? 語法

但如果太阳突然消失一个月，会发生什么？

We were actually inspired to think about this question by the Google Science Fair,

其实，我们是在 Google Science Fair 的启发下开始思考这个问题的。

which is an online global competition for sharing your best ideas using science,

这是一个全球性的线上竞赛，参赛者可以运用科学、

technology, engineering, or math.

技术、工程或数学，分享自己最棒的创意。

I mean, without the sun,

我是说，没有太阳的话，

we'd be requiring some pretty extreme innovations to survive. 用詞

我们得靠一些极具突破性的创新才能活下去。

If you're between the ages of 13 to 18 and have an idea that you think could help shape our world,

如果你年龄在 13 到 18 岁之间，并且有一个你认为能帮助塑造我们的世界的创意，

no matter how big or small, 語法

无论这个创意是大是小，

unique or improving on an existing idea, 短語動詞

是独一无二，还是对现有想法的改进，

you could win an educational scholarship,

你都有机会赢得教育奖学金、

travel experiences, or tons of other prizes.

旅行体验或许多其他奖品。

So stick around at the end of this video for more details. 短語動詞

所以记得看到视频最后，了解更多详情。

Now, after the sun disappears,

现在，太阳消失以后，

for the first 8 minutes and 20 seconds,

在最初的 8 分 20 秒里，

we'd all be completely oblivious, 用詞

我们所有人都会毫无察觉，

as that's how long it takes the sun's light to hit Earth. 語法

因为阳光抵达地球正好需要这么久。

Of course, if it was nighttime where you live,

当然，如果你住的地方当时正值夜晚，

the moon would suddenly disappear,

月亮会突然消失，

as its brightness is simply a reflection of the sun's light.

因为它的亮光其实只是太阳光的反射。

All that's left is the natural light from stars. 語法

剩下的自然光就只有星光了。

Luckily, right now we can still support our electrical systems

幸运的是，目前我们仍能维持供电系统运转，

because 83% of our world's energy comes from oil, coal, and natural gas.

因为全球 83% 的能源来自石油、煤炭和天然气。

Now, because gravity travels at the speed of light too,

而且，由于引力也以光速传播，

it would also take 8 minutes and 20 seconds for Earth to feel the effects of the sun's disappearance.

地球也要过 8 分 20 秒，才会感受到太阳消失带来的影响。

Without the sun's gravitational pull, 語法

失去太阳的引力牵引，

we'd fly out of orbit and into space.

我们会随地球飞离轨道，冲入太空。

But without the light of the sun,

但没有阳光，

all plant photosynthesis would stop immediately.

所有植物的光合作用都会立刻停止。

This is a big deal, 習語

这可是个大问题，

as we need plants for food and oxygen.

因为我们需要植物提供食物和氧气。

In order to survive,

为了生存，

plants need light energy to turn carbon dioxide and water into glucose and oxygen. 短語動詞

植物需要利用光能，把二氧化碳和水转化成葡萄糖和氧气。

Without the sun,

没有太阳，

plants could still photosynthesize with artificial light,

植物仍能借助人造光进行光合作用，

allowing us to grow food, 語法

让我们得以种植粮食，

but these artificial lights could only cover a fraction of the food produced by the sun.

但这些人造光所能维持的粮食产量，只相当于阳光下产量的一小部分。

Currently, indoor farming accounts for 0.07% of agriculture, 短語動詞

目前，室内农业仅占农业总量的 0.07%，

meaning food production would go into crisis.

这意味着粮食生产会陷入危机。

After a week,

一周后，

natural plant life would start decomposing,

自然生长的植物会开始腐烂，

bringing on the collapse of our entire food web. 短語動詞

进而导致整个食物网崩溃。

But another concern is CO2. 表達脈絡

但另一个隐患是二氧化碳。

Decomposition of organic carbon,

有机碳的分解，

like plants and animals,

比如动植物的分解，

accounts for 90% of carbon dioxide already.

本就占二氧化碳排放量的 90%。

Without living plants to uptake that CO2,

没有活着的植物吸收这些二氧化碳，

the atmospheric concentration would skyrocket. 習語

大气中的二氧化碳浓度就会急剧飙升。

CO2 in low concentrations is a physiologically important gas, 表達脈絡

低浓度的二氧化碳是一种对生理功能很重要的气体，

but at high concentrations is toxic.

但浓度过高时就会有毒。

At 1% of our air,

当它占空气的 1% 时，

you'd become drowsy,

你会感到昏昏欲睡，

but greater than 10% would lead to convulsions, coma, and death. 短語搭配

但超过 10% 就会导致抽搐、昏迷和死亡。

As for oxygen, 表達脈絡

至于氧气，

although the brain can only survive 6 minutes without it,

虽然大脑在没有氧气的情况下只能存活 6 分钟，

our atmosphere carries about 1 quintillion kilograms of oxygen,

但大气中含有约 10^18 千克的氧气，

which researchers approximate could last us at least a thousand years. 用詞

研究人员估计，这至少够我们使用一千年。

But within the same week,

不过就在同一周内，

the planet's surface temperature would drop to around minus 18 degrees Celsius,

地球表面温度会降到零下 18 摄氏度左右，

which is survivable for now.

目前人类还可以在这样的温度下生存。

Some Inuit communities already survive Arctic winters that are minus 25 degrees C at the warmest point of the day,

一些因纽特人社区已经能够熬过北极严冬，即使一天中最暖时也只有零下 25 摄氏度，

and some animals can survive minus 60 degrees Celsius.

有些动物甚至能在零下 60 摄氏度的环境中存活。

But the universe is a large and cold place,

但宇宙既广袤又寒冷，

where the ambient temperature of space is around minus 273 degrees Celsius,

太空的环境温度约为零下 273 摄氏度，

meaning it's only going to get colder and colder. 語法

这意味着气温只会越来越低。

After a month,

一个月后，

assuming the same speed as our current orbit, 語法

假设地球仍以目前的公转速度前进，

we'll have traveled 78 million kilometers,

我们就已经行进了 7800 万千米，

putting us past Mars, but not as far as Jupiter. 語法

这会让我们越过火星，但还没到木星那么远。

This may leave us still within what is known as the circumstellar habitable zone, 講解

这可能让我们仍处在所谓的“环恒星宜居带”内，

the orbital range around a star that allows for enough light and heat to support liquid water. 短語動詞

也就是恒星周围光和热足以维持液态水存在的轨道范围。

So, what would happen if after a month the sun suddenly switched back on? 短語動詞

那么，如果一个月后太阳突然重新亮起，会发生什么？

Assuming we haven't crashed into any other planets or had their own gravity impact our trajectory,

假设我们没有撞上其他行星，它们的引力也没有影响我们的运行轨迹，

we're now roughly 170 million kilometers from the sun,

此时我们距离太阳大约 1.7 亿千米，

and it turns out our velocity isn't quite fast enough to escape the sun's gravity at this distance, 講解

而事实证明，在这个距离上，我们的速度还不足以逃脱太阳引力，

so we'd be pulled back into an elliptical orbit,

所以我们会被重新拉入一条椭圆轨道，

though a much wider one than before. 語法

不过这条轨道会比原来大得多。

By most scientific estimates, 表達脈絡

按照大多数科学估算，

we're still within the habitable zone,

我们仍处于宜居带内，

and by congregating around areas that are volcanically and geologically active, 語法

只要聚居在火山活跃、地质活动频繁的地区，

like Iceland and Yellowstone,

比如冰岛和黄石公园，

we could harness the power of our molten core 短語搭配

我们就能利用地球熔融地核的能量，

to make up for the increased distance from the sun to keep us warm. 短語動詞

弥补与太阳距离增加造成的热量损失，让自己保持温暖。

But if the sun had taken a few more months to turn on, 語法

但如果太阳再晚几个月才重新亮起，

we'd be too far to be pulled back into orbit and would become a rogue planet. 講解

我们就会离得太远，无法被拉回轨道，最终变成一颗流浪行星。

Though most planets are tethered to the star that created them,

虽然大多数行星都被孕育它们的恒星束缚着，

studies estimate that within the Milky Way,

但研究估计，在银河系中，

there are 100 billion planets that wander the galaxy as rogue planets.

有 1000 亿颗行星以流浪行星的身份四处游荡。

Whichever the case for Earth,

无论地球最终是哪种情况，

we'd require a lot of human innovation to survive.

我们都得依靠人类的大量创新才能生存下去。

Thanks again to Google Science Fair for sponsoring this video.

再次感谢 Google Science Fair 对本视频的赞助。

If you are between 13 and 18 and you have an idea that could impact the world,

如果你年龄在 13 到 18 岁之间，并且有一个可能影响世界的创意，

make sure you go to googlesciencefair.com.

一定要访问 googlesciencefair.com。

Maybe you have the idea for alternative energy sources

也许你对替代能源有了新点子，

or thought of a way to reduce waste

或者想到了减少浪费的方法，

or just even ask the question,

又或者只是提出了这样一个问题：

couldn't an alarm clock wake you up without making sound?

难道闹钟不能不发出声音就把你叫醒吗？

The deadline to submit your project is December 12th, 2018.

提交项目的截止日期是 2018 年 12 月 12 日。

Maybe you're independent

也许你想独立参赛，

you can submit on your own,

你可以自行提交，

or you can submit as a group of up to three people,

也可以组队提交，每组最多三人，

okay?

好吗？

So check it out,

所以去看看吧，

and also make sure you subscribe to this channel for new science videos every Thursday.

另外别忘了订阅本频道，每周四都有新的科学视频。

See you.

再见。