了解宇宙是如何运行的（2010）

How the Universe Works S08E06

Part 2 Jan. 30, 2022, 2:58 p.m.

“朱诺号♥”探测到氢和岩石物质
juno detects hydrogen
and rocky material
溶解并混合在一起
dissolved and blended together.
这是一种我们从未见过的行星内核
It's a type of planetary core
we've never seen before.
天文学家形容它是模糊的
Astronomers
describe it as fuzzy.
我们还以为能找到鳄梨呢
<鳄梨就是我们喜欢吃的水果——牛油果>
We thought we were gonna find
an avocado.
结果，我们找到了一碗辣椒
Instead, we found
a bowl of chili.
这是氢液辣酱炖肉
It's a hydrogen fluid
chili con carne.
♪
所以我们以前的木星内部模型
so none of our models
of the interior of jupiter
没有一个是正确的
turned out to be correct.
这意味着我们得从头再来
That means we have to go back
to the drawing board.
有一种理论认为
Narrator:
One theory is that jupiter
木星不是由岩石或气体形成的
didn't form from rocks or gas
而是由46亿年前散落在早期太阳系中
but from tiny pebbles
less than an inch wide strewn
不到一英寸宽的小石子形成的
across the early solar system
4.6 billion years ago.
这些鹅卵石聚集在一起
These pebbles came together.
它们聚集形成了一个巨大的物体
They accreted to form
a massive object
就像木星的种子，也就是木星的核心
that was the sort of seed,
the core of jupiter.
这些鹅卵石
Narrator: The swarm of pebbles
聚集在一起形成了一个巨大的星核
clumped together
to form one giant core
它的质量是地球的20倍
20 times the mass of earth,
但是这些鹅卵石不能支撑这个不断增长的星球太久
but these pebbles can't sustain
this growing planet for long.
最终，我们需要从这些
Eventually,
we need to make a jump
厘米大小的粒子跳跃到
from those centimeter-size
particles
真正大的东西，比如100公里的星子
up to really large things, like
100-kilometer planetesimals,
并真正启动一颗行星的生长
to really kick-start growth
of a planet.
♪
随着木星的增长，它的胃口变得无法满足
narrator: As jupiter grows,
its appetite becomes insatiable.
其他可能成为行星的行星核心
The cores of other
would-be planets are drawn in
被木星巨大的引力所吸引，并在撞击时被吸收
by its immense pull
and absorb on impact,
导致木星的核心发生变化
causing jupiter's core
to transform.
大块进入的岩石与气体
Huge chunks of incoming rock
are mixed up with gas
和最初形成星核的鹅卵石混合在一起
and the pebbles
that originally built the core.
我们认为，可能存在于那里的核心物质
We think that core material that
might've been there is actually
实际上已经溶解，并与星球的其他部分混合在一起
dissolved and mixed in
with the rest of the planet.
这种岩石、气体和卵石的混合物
Narrator: This mix of rock,
gas, and pebbles
使核心处于一种奇怪的状态
leaves the core
in a strange state
介于固体和液体之间
somewhere
between solid and liquid
换句话说，是模糊的
or, in other words, fuzzy.
一旦木星的核心达到临界质量
Once jupiter's core reaches
a critical mass,
它的引力就会吸收附近所有的氢气
its gravity pulls
in all nearby hydrogen gas,
形成木星大气层
building the jovian atmosphere
而模糊的核心则被困在
and leaving the fuzzy core
数千英里厚的云层之下
trapped beneath thousands
of miles of thick clouds.
这就是我们今天所知道和喜爱的木星的形成
And that is what formed jupiter
as we know and love it today.
“朱诺号♥”对木星模糊核心的发现
Narrator: Juno's discovery of
jupiter's fuzzy core
可能会改写
could rewrite the book on
关于木星早期的故事，但“朱诺号♥”才刚刚开始
jupiter's early years, but juno
is just getting started.
我们甚至还没有揭开
We haven't even scratched
the surface
神秘事物的面纱
of the number
of mysteries there are.
随着“朱诺号♥”的仪器开始揭示
Narrator: There's more to
jupiter than meets the eye
这个巨大世界黑暗的一面，木星还有更多的东西
as juno's instruments
begin to reveal a darker side
是我们没有看到过的
to this giant world.
木星的环境是太阳系中
Jupiter's environment
is one of the most vicious
最恶劣的环境之一，这是因为
in the solar system,
and that's because
它有着难以置信的强磁场
of its incredibly
strong magnetic field.
“朱诺号♥”就身处其中
Narrator: And juno is caught
right in the middle of it.
♪
巨大的气态巨星木星
narrator: The gas giant jupiter
蕴藏着太阳系奥秘的线索
holds clues to the mysteries
of our solar system,
2011年
and in 2011,
NASA 启动了一项耗资10亿美元的任务来发现它们
nasa launched a billion-dollar
mission to uncover them.
三，二，一，点火
Man: Three, two, one, ignition.
和“朱诺号♥”一起升空的
And liftoff of the atlas v
阿特拉斯五号♥将前往木星
with juno on a trek to jupiter.
为了到达它的目的地
Narrator: To reach its target,
“朱诺号♥”开始了五年的旅程
juno embarks
on a five-year journey.
♪
向其他星球发射任何一艘宇宙飞船
sending any spacecraft
to another planet
都是很困难的，但向木星发射一艘宇宙飞船
is gonna be tough,
but sending one to jupiter
是真的是件非常困难的事情
is really
pushing things pretty hard.
“朱诺号♥”非常精确地
Narrator: Juno weaves through
the solar system
穿越了太阳系
with extreme precision.
这艘飞船与剧烈的温度变化作斗争
The craft battles violent
temperature changes
并小心翼翼地穿越小行星带
and navigates carefully
through the asteroid belt.
如果在你的路径上有一小块尘埃
If there's a fleck of dust
in your path
那东西撞上你的飞船
and that thing slams
into your spacecraft,
就会造成严重的损害
it could do significant damage.
经过了17亿英里（约17亿公里）的跋涉
Narrator: 1.7 billion miles
into its mission,
“朱诺号♥”终于接近了它的目标
juno finally nears its target,
但是探测器正以每小时165000英里（约266000公里）的速度
but the probe is hurtling
towards jupiter
冲向木星
at 165,000 miles an hour.
“朱诺号♥”移♥动♥得非常快
Juno is moving really fast.
它是有史以来速度最快的航♥天♥器之一
It's one of
the fastest spacecraft ever.
你需要足够快的速度才能到达那里
You need to go fast enough
to get there, but then you need
但你又需要足够慢才能被行星的引力捕获
to be slow enough to be captured
by the gravity of the planet.
你的速度得控制地刚刚好
You need to get it just right.
进入木星轨道
Narrator:
Entering orbit around
是任务中最棘手的部分
jupiter is the trickiest part
of the mission.
如果弄错了，“朱诺号♥”可能会撞上行星
Get it wrong and juno could slam
into the planet
或者漂向外太空
or drift out into deep space.
要想成功地让“朱诺号♥”进入木星的稳定轨道
To successfully get juno
to enter a stable orbit around
这几乎就像
jupiter
as almost the same as, say,
从伦敦投篮球
shooting a basketball
from london
然后停留在纽约的篮筐上面
and having it on the land on
the front of the rim in new york
并且要保持平衡一样
and just sitting there
balanced.
我能做到，但 NASA 能在“朱诺号♥”上做到吗？
I could do it, but can nasa
do it with juno?