太阳系——我们在太空中的家：英语精读讲义

The solar system,

太阳系，

our home in space.

我们在太空中的家园。

We live in a peaceful part of the Milky Way.

我们生活在银河系中一个宁静的角落。

Our home is the solar system,

我们的家园就是太阳系，

a 4.5 billion year old formation

这是一个有着45亿年历史的星系，

that races around the galactic center

绕着银河系中心飞驰，

at 200,000 km per hour

速度达到每小时20万公里，

and circles it

绕行一圈

once every 250 million years. 語法

需要2.5亿年。

Our star,

我们的恒星，

the sun,

太阳，

is at the center of the solar system.

位于太阳系的中心。

It's orbited by eight planets,

有八大行星绕其运行，

trillions of asteroids and comets,

还有数以万亿计的小行星和彗星，

and a few dwarf planets.

以及几颗矮行星。

The eight planets are divided into

这八大行星被分为

four planets like ours.

四颗像地球一样的类地行星：

Mercury,

水星、

Venus,

金星、

Earth, and Mars,

地球和火星，

and four gas giants, 文化背景

以及四颗气态巨行星：

Jupiter,

木星、

Saturn,

土星、

Uranus, and Neptune.

天王星和海王星。

Mercury is the smallest

水星是最小

and lightest of all the planets.

也是最轻的行星。

A Mercury year is shorter than a Mercury day,

水星上的一年比水星上的一天还要短，

which leads to enormous fluctuations 語法

这导致了极大的温度

in temperature.

波动。

Mercury does not have an atmosphere

水星没有大气层，

or a moon.

也没有卫星。

Venus is one of the brightest objects 語法

金星是最明亮的天体之一，

in the solar system

在太阳系中，

and by far the hottest planet 短語搭配

也是目前为止最热的行星，

with atmospheric pressure that is 92 times higher 語法

其大气压是地球的92倍

than on Earth.

以上。

An out of control greenhouse effect 講解

失控的温室效应

means that Venus never cools below

意味着金星的温度永远不会低于

437 degrees Celsius.

437摄氏度。

Venus also doesn't have a moon.

金星也没有卫星。

Earth is our home

地球是我们的家园，

and the only planet

也是唯一一颗行星，

with temperatures that are moderate enough 語法

拥有足够适宜的温度，

to allow for a surplus of liquid water.

允许大量液态水存在。

Furthermore,

此外，

it's so far the only place 短語搭配

它是迄今为止已知唯一

where life is known to exist. 語法

存在生命的地方。

The Earth has one moon.

地球有一颗卫星。

Mars is the second smallest planet

火星是第二小的行星，

in the solar system

在太阳系中，

and hardly massive enough to keep 語法

其质量勉强足以维持

a very thin atmosphere.

一层非常稀薄的大气。

Its Olympus Mons is the largest mountain 文化背景

其上的奥林帕斯山是最大的山脉，

in the solar system,

在太阳系中，

more than three times as high as Mount Everest. 語法

高度是珠穆朗玛峰的三倍多。

Mars has two small moons.

火星有两颗小卫星。

Jupiter is the largest and most massive planet

木星是最大、质量最重的行星，

in the solar system.

在太阳系中。

It consists largely of hydrogen and helium 短語搭配

它主要由氢和氦组成，

and is the theater for the largest and most powerful storms 習語

也是已知最大、最强风暴

we know.

发生的舞台。

Its largest storm,

其最大的风暴，

the Great Red Spot, 文化背景

大红斑，

is three times as large as Earth.

面积是地球的三倍。

Jupiter has 67 moons.

木星有67颗卫星。

Saturn is the second largest planet

土星是第二大行星，

and possesses the smallest density of all the planets.

是所有行星中密度最小的。

If you had a sufficiently large bathtub, 語法

如果你有一个足够大的浴缸，

Saturn would swim in it.

土星可以漂浮在里面。

Saturn is also known for its extended,

土星也因其宽广、

very visible ring system.

极其显眼的星环系统而闻名。

It has 62 moons.

它有62颗卫星。

Uranus is the third largest planet

天王星是第三大行星，

and one of the coldest.

也是最冷的行星之一。

Of all the gas giants,

在所有的气态巨行星中，

it's also the smallest.

它也是最小的。

The special thing about Uranus is that its axis of rotation 講解

天王星的特别之处在于其自转轴

is tilted sideways,

是侧倾的，

in contrast to the seven other planets. 表達脈絡

与其他七颗行星不同。

It has 27 moons.

它有27颗卫星。

Neptune is the last planet in the solar system

海王星是太阳系中的最后一颗行星，

and is similar to Uranus.

与天王星相似。

It's so far removed from the sun 語法

它距离太阳非常遥远，

that a Neptune year is 164 Earth years long.

以至于海王星的一年相当于164个地球年。

The highest wind speed ever measured 語法

有史以来测量到的最高风速

was in a storm on Neptune

发生在一场海王星的风暴中，

at just under 2,100 km/h.

接近每小时2100公里。

Neptune has 14 moons.

海王星有14颗卫星。

If we compare the sizes of the planets, 表達脈絡

如果比较各个行星的大小，

the differences between them become even clearer.

它们之间的差异就更加明显。

Jupiter is the leader in terms of size 短語搭配

木星在体积

and weight.

和重量上都是第一。

Small Mercury,

而小巧的水星，

on the other hand, 表達脈絡

另一方面，

is even smaller than one of Jupiter's moons,

甚至比木星的其中一颗卫星还要小，

Ganymede.

那就是木卫三。

Jupiter is so massive

木星极其庞大，

that alone it contains roughly 70% of the mass

仅它自己就包含了所有其他行星

of all the other planets

大约70%的质量，

and has a massive impact on its surroundings.

并对其周围环境产生了巨大的影响。

That's a blessing for Earth,

这对地球来说是个福音，

since Jupiter draws most of the dangerously large asteroids

因为木星吸引了大部分可能摧毁地球生命的

that could wipe out life on Earth. 短語動詞

危险的巨型小行星。

But even Jupiter is a dwarf 習語

但即使是木星也只是一颗矮星，

in comparison to our star,

与我们的恒星相比，

the sun.

那就是太阳。

Calling it massive

称它为庞大

does not do justice to the sun. 習語

都不足以形容太阳。

It makes up 99.86% 短語動詞

它占了99.86%

of the mass in our solar system.

我们太阳系的总质量。

For the most part,

绝大部分

it consists of hydrogen and helium.

由氢和氦组成。

Only less than 2% is made up of 短語動詞

只有不到2%是由

heavy elements like oxygen or iron.

氧或铁等重元素组成的。

At its core,

在其核心，

the sun fuses 620 million tons of hydrogen each second

太阳每秒聚变6.2亿吨的氢，

and generates enough energy

并产生足够的能量

to satisfy mankind's needs for years.

满足人类多年的需求。

But not only the eight planets orbit our sun, 語法

但不仅仅是八大行星围绕着我们的太阳运行，

trillions of asteroids and comets also circle it.

数以万亿计的小行星和彗星也在绕其旋转。

Most of them are concentrated into two belts,

它们大多集中在两个带状区域，

the asteroid belt between Mars and Jupiter

位于火星和木星之间的小行星带，

and the Kuiper belt at the edge of the solar system. 文化背景

以及太阳系边缘的柯伊伯带。

These belts are home to countless objects, 習語

这些小行星带是无数天体的家园，

some as large as a dust particle, 語法

有的只有尘埃颗粒那么大，

others the size of dwarf planets.

有的则像矮行星一般大。

The most well-known object in the asteroid belt is Ceres.

小行星带中最著名的天体是谷神星。

The most well-known objects in the Kuiper belt

柯伊伯带中最著名的天体

are Pluto,

是冥王星、

Makemake,

鸟神星，

and Haumea.

和妊神星。

Usually,

通常，

we describe the asteroid belt 語法

我们将小行星带描述为

as a dense collection of bodies

密集的天体集合，

that constantly collide.

不断地发生碰撞。

But in fact, 表達脈絡

但事实上，

the asteroids are distributed across an area

这些小行星分布在一个区域内，

that is so indescribably large

空间大得难以形容，

that it's even difficult to see two asteroids at once.

以至于很难一次看到两颗小行星。

Despite the billions of objects in them, 語法

尽管其中有数十亿个天体，

the asteroid belts are fairly empty places.

小行星带却相当空旷。

And nonetheless,

尽管如此，

there are collisions over and over again. 短語搭配

碰撞还是会一次又一次地发生。

The mass of both belts is also unimpressive.

这两个带的质量也不算起眼。

The asteroid belt has a little less than

小行星带的质量略低于

4% of our moon's mass.

月球质量的4%。

And the Kuiper belt is only

而柯伊伯带的质量仅在

between 1/25 and 1/10 of Earth's mass.

地球质量的1/25到1/10之间。

One day the solar system will cease to exist. 用詞

有一天太阳系将会不复存在。

The sun will die

太阳将会死亡，

and Mercury,

水星、

Venus,

金星，

and maybe Earth too

也许还有地球

will be destroyed.

也会被毁灭。

In 500 million years,

在5亿年后，

it will become hotter and hotter 語法

温度会变得越来越高，

until at some point

直到某个时刻，

it will melt Earth's crust.

它将融化地球的地壳。

Then the sun will grow and grow

然后太阳会不断变大，

and either swallow Earth 語法

要么吞噬地球，

or at least turn it 短語動詞

要么至少将它变成

into a sea of lava.

一片熔岩之海。

When it has burnt up all its fuel 講解

当它耗尽所有的燃料

and lost most of its mass,

并失去了大部分质量时，

it will shrink to a white dwarf 文化背景

它将收缩成一颗白矮星，

and burn gently for a few billion more years

并安静地燃烧几十亿年，

before it goes out entirely. 短語動詞

直至完全熄灭。

Then at the latest,

到那个时候，

life in the solar system

太阳系中的生命

will no longer be possible.

将再也不可能存在。

The Milky Way will not even notice it.

银河系甚至不会察觉到这一点。

A small part of it

只是在它其中一条悬臂里的

in one of its arms

一个小区域，

will become just a tiny bit darker.

会变得稍微暗淡那么一点点。

And mankind will cease to exist.

人类也将不复存在。

Or leave the solar system

或者已经离开太阳系

in search of a new home. 短語搭配

去寻找新的家园了。