宇宙（2007）

The Universe S05E06

Part 1 April 22, 2021, 1:50 p.m.

In the beginning, there was darkness,
最初宇宙是一片黑暗
and then, bang, giving birth
紧接着一声巨响混沌初开
to an endless, expanding existence of time,
时间空间和物质
space and matter.
开始不断膨胀
Every day,
每天
new discoveries are unlocking the mysterious,
我们都在解密这神秘莫测
the mind-blowing, the deadly secrets
令人疯狂的极端之地
of a place we call the Universe.
那就是宇宙
They've already wiped out the dinosaurs
它们已经毁灭了恐龙
and many other species.
和许多其他物种
And there's no doubt they will strike again.
并且它们必定会再次袭击
It would be a disaster far beyond biblical proportions.
这将是一场远超出圣经中所描述的灾难
Investigating asteroids isn't just about science.
小行星的研究不仅关乎科学
Asteroids are gonna be one of our
小行星对人类来说
biggest problems for humanity.
将是最大的难题之一
It's about survival.
这关乎生死存亡
So, the smarter we can get before then,
所以我们对小行星越了解
the more we can figure out,
越能想出解决办法
can we do anything about it?
我们能做些什么呢
Get ready for the latest asteroid discoveries
为最新的小行星发现做好准备
and daring new plans to go where no man has gone before.
大胆作出前往人类未曾到达之地的计划
It's the year 2029,
2029年
and an asteroid that scientists have been tracking
一颗科学家追踪了数十年的
for decades is passing close to earth.
小行星将在地球附近经过
The asteroid is about three football fields wide.
这颗小行星约为三个足球场宽
Its name is Apophis,
命名为阿波非斯
after the ancient Egyptian God of destruction.
源于埃及神话中的破坏之神
According to the latest predictions
据最新预测显示
Apophis won't hit earth in 2029,
阿波非斯并不会在2029年撞击地球
but as it passes through a seemingly
但是当它经过一个
nondescript area of space nearby,
看似没有特征的空间区域时
the world's scientific community goes on high alert.
整个科学界为之处于高度警戒状态
Astronomers have calculated
天文学家计算出
a very small region of space
一个很小的空间区域
which, if Apophis happens to go through that region,
如果阿波非斯碰巧经过那个区域
then it will be set up for a collision
那它就会在2036年
with earth in 2036.
与地球发生碰撞
And this very, very tiny region,
这个极小的区域
which is less than a mile across,
直径不到一英里
just a few thousand feet across,
仅有几千英尺
is called the keyhole.
其被称为锁眼
An international cooperative of space agencies
一个国际航♥天♥合作机构
launches a rocket to take on Apophis.
发射一枚火箭接近阿波非斯
Now, you don't wanna blow it up with a nuclear weapon.
目前你并不想用核武器炸毁它
First, that would take a lot of energy,
首先那需要很多能量
and it would just produce a huge number of fragments,
同时还会产生大量的碎片
all heading toward the earth.
它们都将涌向地球
What you really wanna do is give it a bit of a push
真正应该做的是给它一点推动力
that slightly changes its trajectory.
轻微改变它的轨道
That way, we don't get a collision.
那样的话就不会发生碰撞
But it's possible that the 30 million ton space rock
但是这个三千万吨♥重的太空岩石
could simply be too massive.
有可能因为体积庞大
The collision hasn't knocked
以至碰撞未能使
the asteroid far enough off course.
小行星偏离足够的距离
The impact in 2036 is thousands of times stronger
2036年撞击所产生的威力
than the atomic bomb dropped on Hiroshima.
会是广岛原♥子♥弹♥爆♥炸♥的数千倍
The immediate crater is as wide as
即刻产生的陨石坑
the island of Manhattan.
如曼哈顿岛大小
It would create a crater over two miles wide.
其将形成一个宽于两英里的陨石坑
If Apophis were to hit a city...
如果阿波非斯撞击某个城市
Goodbye to that city
那这个城市就玩完了
and the surrounding region for 100 miles.
周围一百英里的地区也随之毁灭
From the shock wave, the blast, the winds coming out,
冲击波爆♥炸♥ 狂风大作
from the impact ejecta,
撞击后的喷出物
and from the massive earthquake equivalent
以及进而发生的
that would occur,
等效强烈地震
that would reach out and be felt over huge areas.
这些都会影响到大部分地区
When Apophis was first discovered in 2004,
阿波非斯最早被发现于2004年
the initial odds of an impact were about 1 in 37.
最初判断的碰撞率大概是1/37
But those odds have been dropping over the years,
但近年来碰撞率不断下降
as scientists have obtained a better look at its path.
因为科学家们仔细观测了它的运行轨道
You can make the analogy
可以做这样一个类比
that the orbit determination process
确定轨道的过程
is similar to predicting hurricanes.
和预测飓风差不多
When a hurricane first starts out,
当飓风初形成时
you don't know exactly where it's going to go.
你是不可能预测出精确路线的
And as you get more and more data
在接下来的一两周
in the next week or two,
不断获得更多的数据
then you can refine your predictions.
才能完善预测结果
And so,
所以
it's very much like that with asteroids and comets.
这和确定小行星与彗星的运行轨道极为相似
The more observations you get over time,
观测的时间越长
the better you know
就越清楚
where the object will be in the future.
目标未来的运转轨道
That's why today's odds of an earth impact,
这就是为什么现在预测的与地球相撞的几率
only 1 in 250,000
仅为1/250000
are so much slimmer than the original
这与之前1/37的结果
1 in 37 prediction.
相差甚远
But even if Apophis doesn't hit earth,
即使阿波非斯没有撞击地球
there's no doubt that something else eventually will.
此惨剧必会在未来上演
It's a disaster that space agencies
航♥天♥机构非常重视
take very seriously.
这一灾难
In July 2010,
2010年7月
a NASA advisory panel recommended the creation
美国宇航局顾问团提议创建
of a planetary defense office to figure out
一个行星防御办公室以处理
how to detect and deflect any asteroids
所有向地球而来的小行星的
heading our way.
探测和转向问题
We know for a fact that
我们都清楚
an asteroid is going to impact the earth
一颗小行星将会撞击地球
sometime in the next one to 10,000 years,
在将来的一万年以内的某个时刻
a big one.
小行星的体积还很大
And it's a good question as to when it's gonna happen
值得思考的是撞击何时发生
and are we gonna be ready for it when it does?
那时我们是否能对此有所准备呢
A seaside amusement park is an unlikely place
海边的游乐场不是一个
to demonstrate how asteroids and comets
演示小行星和彗星
speed around our corner of the universe.
撞击地球的理想之地
But an arcade attraction here actually reveals a lot
但是这里的游戏设施却能够充分演示
about these deadly objects.
这些致命天体的撞击过程
Our solar system is kind of like a shooting gallery.
我们的太阳系有些像射击场
Asteroids and comets can occasionally hit
小行星和彗星偶尔撞击
planets and moons,
行星和卫星
creating gigantic impact craters.
撞击后产生巨大的陨石坑
Now, the bigger objects present
目标体积越大
a larger cross-sectional area.
射击可选范围也越大
So, they're easier to hit.
所以很容易就能打中
In this case,
在这种情况下
I actually have to hit these little bull's eyes,
我需要击中这些靶心
which are all about the same size.
它们都是一样大小
But imagine that the man over there is Jupiter.
设想一下那边的男士代表木星
He's big, and the chipmunk might be the earth,
很大这个花栗鼠代表地球
smaller.
小一些
And these ants might be our moon, even smaller.
这些蚂蚁则代表月球更小一些
So Jupiter is pretty easy to hit.
因此木星很容易就被击中
Earth, the chipmunk, is harder to hit.
而地球这个花栗鼠难打些
It's a smaller cross-sectional area.
因为可射击范围小一些
There it goes.
打中了
Earth was hit.
地球被击中了
The ants are small.
蚂蚁很小
So, they're even harder to hit.
所以更难打中了
Most of the asteroids miss.
大部分小行星未能击中目标