恒星七纪（2012）

这样一来 我们用于研究地球的科学方法
and therefore scientific processes that were applied to the Earth
也可以用来研究太阳
could also be applied to the Sun.
以此为基础 我们才有了随后的新发现
This underpins our subsequent discoveries
关于太阳 其他恒星和整个天文学
about the Sun, the other stars and all of astronomy, really.
基于伽利略的工作
Building on Galileo's work,
科学家们还发现
scientists have discovered
正是太阳活跃多变的特性
that the Sun's active, changeable nature, is in fact,
给我们带来了最直接的影响
the characteristic that has the biggest impact on us.
他观察到的黑子与太阳耀斑有关
The sunspots he observed are linked to solar flares.
耀斑爆发瞬间会释放巨大的能量
Sudden, colossal releases of energy
将数百万吨♥的物质抛向太空
that can spew over a million tonnes of material into space.
这股带电粒子流
This stream of charged particles
能够扰乱卫星通讯
is able to scramble satellite communications -
极端情况下 甚至能使电网瘫痪
in extreme cases, knock out power grids.
而这一切都源于
And all caused
太阳磁场的湍动特性
by the turbulent nature of the Sun's magnetic field.
有时 部分太阳磁场会缠在一起
Sometimes these magnetic fields get twisted up.
磁力线的足点到处移♥动♥ 磁力线错综交缠
The foot points move around, and they get really twisted up,
足点 磁力线汇聚的地方
局部磁场变得异常复杂 最终磁力线断裂
and they get so knotted up that eventually they crack and break.
这样就会爆发一场巨大的太阳耀斑
And we have solar flares, huge explosion.
粒子被喷向太空
Particles are shot out into space.
我们最近观察的
In fact, this little active region,
这块活动区域
I mean, it's quite big, actually,
范围其实还挺大的
that we've been looking at recently,
过去的几天里一直在喷射耀斑
has been flaring continuously over the past few days.
尽管这种剧烈的喷发对我们有害
But while the Sun's violent outbursts can harm us,
但正是太阳活动才让我们得以生存
its active nature is what allows us to live at all.
因为太阳也会喷射太阳风
Because the Sun also ejects the solar wind,
它们是被抛向太空中带电粒子流
an energised stream of particles that head out into space.
当粒子流撞上大气层时
And that we can see passing Earth
我们就能欣赏到
as it bounces off our atmosphere...
美丽的极光
..The aurorae.
太阳风继续飘往远方
Then the solar wind flies on.
在木星的两极绘出同样绮丽的辉光
Putting on the same show at the poles of Jupiter...
然后来到土星
..And Saturn too.
最终在日地距离一百倍以外
Until, finally, 100 Earth Sun distances away,
太阳风势头减弱
it loses its momentum
在宇宙中 形成太阳系的边界
and forms a boundary with deep space...
吹出了一个保护泡
..Creating a protective bubble
使我们所处的太阳系
that shields our solar system
免受银河辐射和宇宙射线的伤害
from dangerous galactic radiation and cosmic ray -
这就是日球层
the heliosphere.
在日球层的保护下
Within it, life on a planet
一颗距离适中的行星就能孕育生命
just the right distance away can thrive.
太阳要不断地核聚变来抵抗重力
We are beneficiaries of the energy the Sun generates
而我们就受益于其中产生的能量
as nuclear fusion fights back against gravity.
能量不会凭空出现或消失 只会转移
Energy isn't created or destroyed, it's transferred,
能量从太阳的核心 穿过大气
so it's transferred from the centre of the Sun
以多种形式转移到我们身上
through the atmospheres to us, in many forms,
阳光和热量
warmth and light,
经由植物 粮食 养育了我们
via the plants and via the food that we eat.
当清晨的阳光洒向巨石阵
'As dawn throws into shadowy relief
在石柱间投下清晰的光影
'the giant pillars of Stonehenge,
古老德鲁伊祭司的传人
'the successors of the ancient Druids
准备迎接夏至日的第一缕阳光
'await the first rays of midsummer Sun.'
我非常理解
I can really understand
古人为什么会崇拜太阳
why ancient civilisations would have worshipped it,
因为太阳就像神一样
because it is like a god in a sense of it
为我们提供了所有的必需品
provides everything that's so important,
没有了太阳 生命将不复存在
that without it, the... life would cease to exist.
古人担心太阳将不再升起
Ancient man was right to worry whether the Sun
并非杞人忧天
would rise again.
它已经燃烧了五十亿年
It's been burning for five billion years,
但它一半的氢燃料 已经用于核聚变
but it's now used up half its hydrogen fuel
来抵抗重力了
resisting gravity.
某天清晨 太阳将最后一次眷顾地球
One morning, the Sun will rise on a last perfect day on Earth.
我们以前无从预测末日将何时来到
For many years, we had no idea when the end would come.
但我们现在却能解读太阳的命运
But now we can predict the Sun's fate...
和我们自己的命运
and our own.
这并非来源于对太阳的研究
We've learnt it, not by studying the Sun,
而是来自对其它众多恒星的观测
but by observing all the other stars in the sky.
这一突破性进展
The breakthrough came
源于美国天文学家亨利·诺利斯·罗素
when American astronomer Henry Norris Russell
和丹麦人埃希纳·赫茨普龙的研究
and the Dane, Ejnar Hertzsprung,
他们试图为夜幕中
tried to create a pattern
所有的恒星建立一个普适的模型
that made sense of all the stars in the night sky.
不论恒星是大是小
No matter what their size,
也不论它们明亮还是黯淡
or whether they burned hotter or dimmer.
这一模型向我们揭示了恒星的生命循环
This finally revealed that stars had a lifecycle.
在二十世纪之交
At the turn of the 20th century,
天文学家已经积累了大量的恒星观测资料
astronomers have already a wealth of data about the stars.
主要测量了恒星的颜色
Mainly, they have measured the colours
和它们的真实光度
and the real luminosities of them.
赫茨普龙和罗素所做的
So what Hertzsprung and Russell did
就是把恒星
was to organise the stars
弗朗西斯科·迭戈博士
伦敦大学学院 天文学家
按照温度和光度 排列在一张图上
in order of temperatures and in order of luminosities,
这样就画出了赫罗图
and this is the birth of the Hertzsprung-Russell diagram.
假设他们离地球距离都相同
On one axis, they plotted how bright the stars would be
其中一个轴代表恒星的亮度
if they were all the same distance away from us,
由最暗的到最亮的
from the dimmest to the brightest.
另一个轴代表恒星的温度
On the other axis was their temperature,
由恒星的颜色来表示
as indicated by their colour,
从温度高的蓝白星 到较冷的红星
from blue and white hot to cooler red.
经排列后的恒星展示出了神奇的规律
What was revelatory was the pattern that emerged.
几乎所有恒星都落在了图中♥央♥的对角线上
Almost all the stars fell into a central diagonal line,
这条对角线称为主序带
known as the main sequence.
主序带上的恒星都尚处中年
These are the middle-aged stars,
内核中还储有足够的氢
ones who still have enough hydrogen in their cores
可以聚变为氦来抵御重力塌缩
to fuse into helium and resist the force of gravity.
但在主序带两侧还有两小群恒星
But on either side were two small outcrops.
在解读赫罗图的过程中 科学家们发现
By deciphering the diagram, scientists discovered
这两块边缘群体预示了太阳的未来
that these outlying groups predicted the future of our Sun.
现在太阳还在燃烧氢
Now, the Sun will be burning hydrogen,
所有主序星都如此
as the stars do in the main sequence,
但当内核的氢被耗尽的时候
until the hydrogen is exhausted in the core,
主序星就要开始走向死亡了
and at that point, the star starts to die.
太阳的外层会开始膨胀
The outer layers of the Sun will expand.
它会渐渐脱离主序带
The Sun will move away from the main sequence
成为一颗红巨星
to become a Red Giant star.
夜空中繁杂的恒星
From the apparent disorder of the night sky,
构成了一副简单的图谱
a map had been created...
在这张图上你可以勾画出恒星的一生
..On which you could chart a star's journey through life.
它告诉我们 太阳的命运
It revealed that the fate of our own star
就写在夜空中
was written in the night sky.
当太阳内的氢消耗殆尽
Once its hydrogen runs out,
它将脱离主序带
it will head off the main sequence
进入它生命中的下一篇章
and move into the next phase of its life,
成为一颗红巨星
as a Red Giant.
像太阳这样中低质量的恒星
Middleweight stars, like our Sun,
不会优雅地老去
don't age gracefully
而会制♥造♥一场灾难
but catastrophically.
他们会膨胀成为宇宙中数一数二的
They swell up and become some of the largest,
无比巨大的恒星
most bloated stars in the universe.
参宿四 猎户座
变成比太阳大两百倍
Stars 200 times the size of our Sun.
亮几千倍的恒星
Thousands of times brighter.
心宿二 天蝎座
变成宇宙中最具破坏性的恒星
Stars that are some of the most destructive in the universe
但它们也最具创造力
but also the most creative,
为漆黑的天空撒上点点猩红