宇宙（2007）

The Universe S01E05

Part 2 April 22, 2021, 8:11 p.m.

撞击是如此的沉重和直接.
The result looks very much like the bull's eye on a target.
看上去非常象靶子上公牛的眼睛.
This Orientale scar is kind of like a bullet shot in the glass, where you see all the
这个东方之海就象子弹射在玻璃上,
the sort of rings around it and fractures going out.
能够看到全部的环状物,碎片喷出来.
People have often said that if it had been on the side facing directly toward you,
人们经常说,如果它处在直接对着地球的一面,
we might have had a whole different mythology about the Moon,
我们就可能会有月球的其它神话了,
because it will look like a big eye staring at us.
这是因为它就象一个大眼睛注视着我们.
Three concentric rings of mountain ranges surround Mare Orientale,
叁个山脉组成的同心环围绕着东方之海,
and some of the peaks rise to several thousand feet.
有些山峰高达几千英尺.
They're all effects of the monster impact.
它们是猛烈冲击的产物.
When we see mountain ranges on the Earth, they're mostly caused first by
当我们在地球上看到环型山,这些首先是由
the continents moving around, crashing into each other very slowly, buckling up and
周围的陆地运动造成的,陆地相互之间的运动非常缓慢,
creating mountain ranges which then erode into all that spectacular
折皱产生环型山,并且在水的侵蚀以后,
shapes that we see at the Matterhorn and so forth, from water erosion.
才形成我们在马特洪峰看到的壮观景象.
On the Moon, there are no continental plate tectonics.
在月球上,没有大♥陆♥板块运动.
The surface is static.
表面是静止的.
Yeah. You still have mountains on the Moon
是的.在月球上还是能看到山脉,
and the reason is that those big impact basins.
原因在于那些巨大的撞击盆地.
That's big explosion excavates a pit,
那是一个巨大的喷发陷坑,
throws the material up on the outsides, so you have these rings of mountains,
物体投掷在外面,所以会有环形山,
arcs of mountains, that surround the impact sites.
弧形山,包围着撞击的地点.
But their impact features in there is caused by the external forces,
然而这些撞击特征是由外部力量引发的,
not the internal forces.
而不是内部力量引起的.
Another notable impact crater, much smaller than Mare Orientale,
另一个引人注目的撞击坑,要比东方之海小许多,
but every bit as spectacular, is Tycho.
但非常壮观,叫第谷.
Named after a prominent 17th century Danish astronomer,
是以17世纪一位着名的丹麦天文学家的名字命名的,
this impact feature
这个撞击坑
is located in the southwestern quadrant on the Moon's near side.
坐落在月球西南方的边缘处.
It's... in the bright area, you could have almost see it with the naked eye.
它是...在明亮的区域,用肉眼几乎就能看到它.
And when that explosion happened as with many other craters
当它爆发时,就象其它许多弹坑一样,
it shot out jets of bright powdery dust,
喷射出明亮的粉尘,
so that these rays that got out from it were very stripy.
所以这些喷发的放射状条纹很清楚.
The rays of dusty ejected material extends some 900 miles from the Tycho impact site.
喷射出来的放射状物质从第谷的碰撞点向外延展了900英里.
A mountain of debris also rises from the center of the crater.
一座残留的山体也在弹坑的中心升起.
This is a result of recoil from the asteroid's strike.
这是小行星撞击的反作用力造成的.
Some of the highly compressed material at the center of the impact site
在那个撞击点中心的一些被高速压扁的物质
springs outward, once the impacting body either ricochets or disintegrates.
向外弹出,一旦撞击,要么弹起,要么粉碎.
But long before any of the Moon specific features
然而长♥期♥以来,所有的月球特征
could be discern through sophisticated telescopes and space travel,
都已经通过望远镜和太空旅行了解清楚了,
careful observation of the lunar behavior and appearance
对月球的外貌和举止行为的仔细观察
was still vitally important to Earth dwellers.
对地球的居民来说仍然是至关重要的.
For 15,000 years at least, Man revered the Moon as a source of light,
至少在15000年里,人类敬仰月亮作为光的来源,
as a navigational guide,
作为航海的指南,
as a reference in agricultural pursuits.
作为农业生产的参考.
And most of all... as a convenient timekeeper.
而最重要的是...作为方便的计时器.
In the days before our modern systems, timekeeping was no simple task.
在现代社会之前的日子里,计时可不是件容易的事.
Early timekeepers had two choices:
早期的计时有两种选择:
they could monitor the Sun or the Moon.
依靠太阳或者月亮.
If you think about trying to keep track of dates,
如果你想记录日期,
if you use a solar calendar like we do nowadays,
如果你用我们现在使用的阳历计时,
there are 365 days in a year, and that's an awful lot of days to keep track of,
一年就有365天,那就要持续记录大量的天数,
and it's not something that the ordinary person could do very well.
这是一件平常人难以做好的事情.
Compare that with a lunar calendar. Everybody can tell when the full moon is
相对的是用阴历.谁都会告诉你月亮什么时候处在满月,
when the new moon is, you don't see the moon at new moon,
月亮什么时候处在新月,用不着看月亮是不是新月,
you see it as big and round at full moon so it's easy to tell,
只要将月亮与满月做个比较很容易就告诉你了,
there are only 28 or 29 days in a lunar cycle, so it's easy to count them
月亮的周期只有28或29天,很容易计算,
and so most societies actually started out with a lunar calendar.
所以大多数民族还是用阴历的.
Early observers of the Moon also recognize that our planetary neighbor
早期的月球观察家也承认那颗我们星球的伙伴
has a very real physical effect on the Earth itself.
对地球有着非常的物理作用.
The Moon is responsible for the rise and fall of our ocean tides.
月球与我们的海洋的潮汐涨落有关.
If I think of the Moon as being this tennis ball
如果月球是这个网球,
and the Earth as being this football,
地球是这个足球,
the tides are caused by the Moon's gravitational attraction,
潮汐是由月球的引力引起的,
so it's obvious... Ok, so the Moon kind of pulls the Earth's water towards it.
这是显而易见的...这样,月球的力量牵引着地球上的水.
And so this creates a slight bulge in the direction of the Moon.
所以这造成了朝着月球的方向稍微有些隆起.
Well, it's less obvious that there's also a bulge in the direction away from the Moon,
同样,在背对月球方向的地方也稍微有些隆起,
so there is in fact two high tides every day.
这事实上就是每天两次高♥潮♥的原因.
The other high tide you can think of is being caused
其它高♥潮♥你能够想象到是由
by the Earth's centripetal force.
地球的向心力引起的.
The Earth and the Moon are both rotating around, and that causes
地球和月球两者轮流运转,引起
the water on the far side to also move out.
远处的水同样运动.
An extreme illustration of the difference between high and low tides
涨潮和落潮之间差异的一个极端的例子
can be found along the shore of Canada's Bay of Fundy.
可以在加拿大芬迪湾看到.
The water level from high tide to low tide
涨潮和落潮之间的落差
drops an astounding 55 feet.
竟然达到55英尺.
For some forms of life on Earth,
对地球上的某些生命来说,
the advance and retreat of the tides creates useful habitats.
涨潮和落潮创造了有益的环境.
But another of the Moon's gravitational effect on our planet
然而月球对我们星球的另一个引力作用,
is directly responsible for nothing less
是直接作用陆地生存的生命.
than the continued survival of terrestrial life itself.
The Moon stabilizes Earth's climate. The gravitational effect of the Moon
月球稳定地球的气候.月球的引力
keeps the degree of tilt on the Earth's rotational axis constant.
使得地球的自转轴倾斜保持在一定的角度.
This tilt is what maintains the repeatable cycle of seasons,
这个倾斜保持了季节的周期,
as the Earth orbits the Sun.
随着地球围绕太阳运转.
If we didn't have the Moon, or if we had a much smaller Moon, for example,
如果我们没有月球,如果我们没有一个小许多的月球,举个例子,
then you can mathematically show,
可以通过计算看出,
that the tilt of our north pole would vary widely,
我们的北极的倾斜会有很大差别,
with that angle going, from, say, 0 to 90 degrees, currently it's 23.5 degrees,
换角度来说,从0到90度,现在是23.5度,
and it would actually vary chaotically.
事实上那将会很混乱.
And so the Moon has played an important role in the stability
所以月球在稳定我们的旋转轴,
of our axis of rotation, of our planet and therefore in our climate.
稳定我们星球和气候方面扮演了重要的角色.
Over the millennia, with the Moon's prominent
在过去的年代里,由于月球
and constant presence in our night sky,
始终如一地挂在天空,
man ultimately began to speculate on its origin.
人们终于开始推测它的来历.
How did it form? How did the Moon come to be?
它是如何形成的?月球是怎么来的?
In 455 BCE the Greek scholar Anaxagoras
公元前455年,希腊学者Anaxagoras
theorized that the Moon was simply a rock that was flung off by the Earth.
推断月球只是地球甩出去的一块石头.
Most of his contemporaries, on the other hand,
而此时,大多数他的同时代的人
were convinced that the Moon was a god,
却深信月球是神灵,
or maybe a huge ball of fire.
或可能是个巨大的火球.
So Anaxagoras' notion did not get much attraction.
所以Anaxagoras的想法没有得到更多的关注.
Quiet speculation no doubt continued,
冷静的思考毫无疑问还在继续,
but no hard information about the Moon came until 1609.
但一直到1609年都还没有过硬的说法.
When Italian astronomer Galileo Galilei
当意大利天文学家伽利略
pointed one of the first telescopes at the Moon,
首次用望远镜对准月球时,
recognized that he was looking at a landscape, the terrain of another world.
验证了他所看到的景观是另一个世界的地形.
When you look at the Moon through a telescope,
当你通过望远镜观看月球,
it looks completely different from the way it looks to the naked eye.
看到情况与肉眼看到完全不同.
So instead of looking flat the way it does to the naked eye,
所以肉眼看到的平坦的景象被替代了,
it really looks round, and you can see the shadows,
环望四周,都是阴影,
you can see all these craters that a naked eye just not see,
看到的都是弹坑,肉眼是看不到的,
and it just immediately looks like a world,
只是一眼看上去象个宇宙,
it jumps out at you into three dimensions.
从叁维世界里跳了出来.
Galileo made detailed drawings of the small planet's surface,
伽利略详细地描绘了小行星的表面,
and established once and for all that the Moon is a solid world,
并且永远确立了月球是固体的星球,
not a god or a fireball.
不是神灵或火球.
But the groundbreaking astronomer never publicly speculated on the Moon's origin.
然而这位天文开拓者从未公开推测月球的起源.
Primarily because he hasn't assume move to other planets.
首先是因为他假设那是颗其它的行星.
Not until 1873
不过直到1873年,
did the first science based theory regarding the origin of the Moon
关于月球起源的科学理论才
publicly emerge.
首次公开♥发♥表.
It sprang from the mind of a talented French astronomer named Edouard Roche.
是从天才的法国天文学家Edouard Roche头脑里涌现出来.
Roche advocated for what's called the co-accretion theory,
Roche鼓吹所谓的共同成长理论,
which says that basically
那主要是表明,
Earth and the Moon grew up at the same time, out of the same materials.
地球和月球是在同一时间形成,由相同物质组成的.
In Roche's days many scientists began to believe
那时许多科学家开始相信
that the planets might have formed from hot condensing clouds of gas.
行星是由冷凝的气体云形成的.
It gradually contracted and cooled and as it contracted,
它逐渐收缩冷却,并且随着收缩,
it would separate out rings of gas, so you'd have
分离气体环,
a ring of gas here, a ring here and so forth.
所以气体环在这里,一个环在这里,等等.
And these rings of gas would then eventually coalesce and form the planets.
这些气体环最后终于凝结形成行星.