了解宇宙是如何运行的（2010）

How the Universe Works S09E02

Part 9 March 16, 2022, 8:54 a.m.

On the Earth,
沙丘是由这种大小的颗粒组成的
the sand dunes are made of
grains about this size.
但在彗星上，沙丘颗粒的大小是这样的
But on the comet, the sand
dune grains are this size.
在彗星上的移♥动♥颗粒的过程中
Gravity also plays
a really important role
引力也起着非常重要的作用
in moving grains
around on the comet.
彗星的密度非常低，如果在周围走动
The comet has such a low
density that if you were
可以很容易地飞进轨道
walking around, you'd be able
to fly into orbit very easily,
所以这么大但密度很低的颗粒
and so a grain this big but
low density would easily be
很容易被那里非常稀薄的空气抛起
lofted by the very thin
air there.
在与67P彗星围绕太阳运行了两年之后
After two years orbiting
the sun with Comet 67P,
“罗塞塔”的任务几乎结束了
Rosetta's mission
was almost over.
所以计划是以一种可控的方式
So the plan was
to lower the orbiter
将轨道飞行器降落到彗星表面
down towards the surface
in a controlled way.
这将可能拍摄非常高分辨率的图像
And this would allow very
high-resolution images to be
也可以在彗星表面附近
taken and also to get some
gas measurements right
进行一些气体♥检♥测
close to the surface
of the comet.
2016年9月30日
September 30th, 2016.
“罗塞塔”花了14个小时缓慢地以自♥由♥落体的方式
Rosetta spent 14 hours
slowly free-falling
向彗星坠落，并在坠落过程中拍摄照片
towards the comet,
taking photos on the way down.
谢里丹:随着“罗塞塔”号♥降落，它接触到彗星表面
SHERIDAN: As Rosetta was
lowered, it touched the surface,
然后与地球的联♥系♥就中断了
and then the link back
to Earth was broken,
任务实际上就结束了
and the mission was
effectively over.
它的奇妙之处在于
The thing that's kind of
wonderful about it is
在那颗彗星上现在就有
that there's
a little piece of us
我们人类的一小部分
on that comet
out there right now.
这颗彗星每隔6.5年
As that comet spins around out
就会绕木星转一圈
to Jupiter and back every
6.5 years,
彗星上将永远有一些人类的影子
it will always have a little
bit of humanity on it.
“罗塞塔”的故事还有最后一个转折
There was one final
twist to Rosetta's story.
杜尔达:我们以为我们拿到了“罗塞塔”号♥
DURDA: We thought we had
the last image back
在计划任务结束前传回的最后一张图像
from Rosetta before
the planned end of the mission.
但事实证明，就在着陆之前
But it turns out that actually,
在能够完全把数据
just before touching down,
before the come were able to
传回地球之前
finish transmitting back to
一个不完整的信息包被发送了回来
Earth, an incomplete packet of
information was sent back.
计算机丢弃了这个不完整的数据包
The computer discarded
this incomplete data packet.
最近，人类专家重新检查了它
Recently, human experts
re-examined it.
结果……“罗塞塔”最近的67P照片
The result...
Rosetta's closest photo of 67P.
这张图片很神奇，因为当你把它放大
And the image is amazing,
because when you actually blow
看着它，你会觉得
it up and look at it,
you can actually feel like
你真的可以伸手去摸它的表面
you could reach out
and touch the surface.
这是对唯一一次登陆彗星的任务的
It's a fitting postscript to
适当补充
the only mission to land on
a comet.
杜尔达:这是一个极好的机会，可以了解那里的地质构造
DURDA: It's an incredible chance
to learn about the geologic
完全不亚于人类在那里探险的
structure at the size scale of
规模……这是我们以前从未见过
a human being exploring there...
It's a way to look at comets
一种观察彗星的方式
that we've never had before.
罗塞塔任务改变了我们对彗星的
The Rosetta mission has
transformed our understanding
理解
of comets.
沃尔什:通过发现奇怪的形状和
WALSH: Between the strange shape
and the measurements of
对重水的检测，我们发现
heavy water, we're finding
彗星的多样性很大
that there's a big diversity
out there of comets,
之后我们每次去参观一个新的彗星
and that every time
we go to visit a new one,
我们可能会再次感到惊讶
we're probably gonna be
surprised all over again.
“罗塞塔”可能会激发新的任务
Rosetta may inspire
new missions.
泰勒:我们可能会再次回到67P彗星
THALLER: We may actually be
returning to Comet 67P itself.
关于我们生命的起源，关于我们自己
There's a lot more there
to discover
在地球上还有很多
about the origin of
our lives, ourselves,
有待发现的地方
here on Earth.
还有很多东西要研究
There's so much more to learn
还有很多谜团要揭开
and so many more mysteries
to uncover.