行星（2019）

美国国家航♥空♥航♥天♥局“信使”号♥水星探测器发射升空
Lift off of Messenger on NASA'S mission to Mercury.
水 星
金 星
火 星
木 星
土 星
天 王 星
海 王 星
行星 第2集
火星 距离太阳2.3亿公里
地球的邻居火星是一颗寒冷贫瘠的岩石行星
Our planetary neighbour, Mars, is a cold, barren rock.
火星的表面 因为覆盖着炙热的沙土 呈现出锈红色
Its rusted surface covered in parched sand.
但隐藏在沙尘之下的
But, beneath the dust,
一些痕迹说明火星曾存在生命
the planet bears the scars of a former life.
数十亿年前 火星几乎与地球无异
Billions of years ago, Mars was just like Earth.
那时 火星上厚厚的大气层
A world with a thick atmosphere
为海洋的存在提供了保障
that supported oceans of water.
但如今 这个世界已不复存在
But, today, that world is gone.
火星已死
Mars lies dead,
而地球仍充满生机
while the Earth thrives.
两颗行星的命运如此不同的原因 仍然是不解之谜
Why the two planets had such different fates is a mystery
我们刚刚开始探索其中的奥妙
that we've only just begun to answer.
两颗姐妹行星 地球与火星
火星
你们看到夜空中那个淡红色的光点了吗
You see that pale red point of light in the sky,
就在那边
just there?
那就是火星
That's Mars.
通过小型望远镜观察 它看起来几乎和地球一样
Through a small telescope, it appears almost Earth-like.
19世纪的天文学家 曾在地球的姐妹行星上
Our sister world - polar ice caps and dark surface
观测到极地冰盖和黑色的表面阴影 他们认为这是植被
markings that 19th-century astronomers thought were vegetation,
甚至是将极地融雪水引入干旱的
even canals bringing meltwater down from the poles
赤道城市的河道
to arid equatorial cities.
赫伯特·乔治·威尔斯曾写道
Across the depths of space,
在太空的深处有居民嫉妒地注视着我们
the inhabitants watched us "with envious eyes", wrote HG Wells.
我们现在知道火星上并没有生命在注视我们
We now know that there are no eyes looking back at us.
火星是一个寒冷 干旱的沙漠世界
Mars is a frozen, arid desert world.
但太空探测器的观测结果表明
But a fleet of spacecraft have revealed
情况并非一直如此
that it hasn't always been that way.
“水手”4号♥探测器成功发射
Mariner 4 was successfully launched on time
“水手”4号♥探测器 196♥4♥年
开启具有历史意义的228天火星之旅
for its historic 228-day journey to Mars.
1965年7月15日 “水手”4号♥开始回传照片
Picture information started to come in on July 15th, 1965.
首张火星表面清晰图像
这个突破可与伽利略首次通过望远镜
A revelation comparable to Galileo's first view
观测到月球相媲美
of the moon through a telescope.
“水手”4号♥短暂飞过火星上空
During its brief flyby,
首此为我们传回了火星的近景照片
Mariner 4 gave us our first close-up glimpses of Mars.
“水手”9号♥探测器 1971年
当“水手”9号♥探测器进入环绕火星的轨道时
When Mariner 9 was placed into an orbit around Mars,
火星正被一场巨大的沙尘暴笼罩
it saw a planet blanketed by a gigantic dust storm.
在近一年的绕轨运行
In nearly a year of operation,
“水手”9号♥传回了7000多张照片
they transmit more than 7,000 photographs.
“水手”9号♥在轨道上拍到了80%的火星表面
From orbit, Mariner 9 photographed 80% of the Martian surface.
维京计划 1975年
首先 它有两只眼睛 可以拍摄到彩色的立体照片
First of all, there are two eyes, not only in colour but also
同时它还带有红外线光储仪
in stereo, and in the infrared part of the spectrum.
它有触觉和听觉
It has a sense of touch, it has a sense of hearing,
但这台探测器最重要的特点是它的大脑
but by far the most important feature of the lander is its brain.
“维京”号♥探测器首次将我们带到
The Viking programme took us down to the ground
火星表面
for the first time...
“维京”号♥在火星安全着陆
着陆 我们着陆了
Touchdown, we have touched down.
它揭示了一个
..and revealed Mars...
完美着陆
Perfect set-down.
前所未见的火星
..like never before.
这是传回的第一条信息
There is the first piece of information coming in.
火星表面的首张彩色照片
利用过去50年收集的数据 我们可以绘制出
The data gathered over the last 50 years has allowed us to create
火星表面的详细图像
detailed maps of the Martian surface...
并尝试拼凑出它的过去
..and begin to piece together its past.
火星的地图就像一本本故事书
Maps of Mars are like storybooks.
你可以读到写在火星表面的历史
You can read the history of the planet
这是因为它基本没有被腐蚀
written across its surface, and the reason for that is that there's
数十亿年来 火星表面一直没有被腐蚀
virtually no erosion, hasn't been for billions of years,
因此40亿年前留下的痕迹
so the scars of events that happened even four billion years ago
依然清晰可见
can still be seen.
这种地图被称为地形高程图
This is a type of map called an elevation map.
不同的颜色对应火星表面不同的高度
The colours correspond to difference in heights on the surface,
蓝色表示高度较低
so blue means low
红色或白色表示较高
and red and whites are high.
这个区域的高度大于火星其它区域的平均高度
Now, this region here, which is much higher on average than the rest
被称为塔尔西斯 这里被火山覆盖
of Mars, is called Tharsis and it's covered in volcanoes,
包括太阳系最大的火山 奥林匹斯山
including the largest volcano in the solar system, Olympus Mons.
奥林匹斯山
塔尔西斯的另一侧 是宽大延展的水手谷
At the other side of Tharsis is the great Valles Marineris,
在这个峡谷面前 地球上所有的峡谷
the Mariner Valley, and it is a canyon that dwarfs
都相形见绌
anything we see on Earth.
水手谷
火星的另一侧是一个被称为赫拉斯盆地的冲击盆地
On the opposite side of the planet is an impact basin called Hellas.
赫拉斯盆地
从火山口边缘到火山口底部的高度差
The height difference from the crater rim
是9000米
to the crater floor is 9km.
这意味着我们可以将珠穆朗玛峰放在它的中间
That means you could fit Everest in the middle of there
还可以俯瞰珠穆朗玛峰的顶峰
and look down on its summit.
盆地周围的地区揭示了火星过去存在生命的迹象
And the region surrounding the basin reveals Mars' former life.
赫拉斯盆地也是火星存世最古老的地带 遭受冲击形成的
The Hellas basin is punched into the oldest-surviving terrain on Mars.
这片地形被称为诺亚台地
It's called Noachis Terra
或诺亚之地
or The Land Of Noah.
这个名称非常形象 因为它的表面是由流水
And that's a wonderfully evocative name because its surface is sculpted
雕蚀而成的
by flowing water.
诺亚台地
我们在最古老的火星表面发现了
All across the earliest Martian surface, we've glimpsed traces
湖泊和河流的痕迹
of what appear to have been lakes and rivers.
新一代的太空探测器被送往火星
And so a new generation of spacecraft has been sent to Mars,
美国国家航♥空♥航♥天♥局 “火星大气与挥发物演化”探测器大气分♥析♥
探索火星上是否存在水
to investigate the existence of water...
美国国家航♥空♥航♥天♥局 火星勘测轨道飞行器拍摄火星表面
这里又发生过什么 水会消失不见了
..and what happened to the planet for it all to disappear.
这是史上最大胆的火星任务
Led by the most audacious Mars mission ever attempted...
我们在火星轨道附近遭遇了两次冲击
We have two-way Doppler and orbit around the planet Mars.
美国国家航♥空♥航♥天♥局“好奇”号♥火星探测器
将一吨♥重的探测器送到火星表面
..to land a one-tonne rover on the Martian surface.
最后它经受了著名的“恐怖七分钟”
Its final descent has become known as the "seven minutes of terror".
“好奇”号♥火星探测器成功登陆盖尔撞击坑
Curiosity touched down in Gale crater,
盖尔撞击坑的宽度为150公里
a 150-kilometre-wide impact basin,
科学家认为这里曾存在一个古老的湖泊
thought to have been home to an ancient lake.
“好奇”号♥火星探测器耗资25亿美元 是一个移♥动♥的化学实验室
The rover is a 2.5 billion mobile chemistry lab...
它的任务是在火星表面提取样本
..designed to take samples of the Martian surface
并分♥析♥样本成分
and analyse its composition.
“好奇”号♥在探索撞击坑的同时 发现了被水流
As it explored the crater, Curiosity saw pebbles polished
磨光磨圆的鹅卵石
and rounded by running water
这里曾是河水流经之地
in what had once been rivers and streams.
“好奇”号♥在着陆61天后 找到了理想的地点
Then, 61 days after landing, Curiosity identified the perfect
开始实施它的首要任务
spot to begin its primary mission.
撞击坑里有一块名为“岩巢”的沙地
In a sandy area of the crater called the Rocknest,
探测器在这里首次收集到了火星的土壤
the rover took its first scoops of Martian soil.
探测器对这些细沙进行化学分♥析♥
Chemical analysis of the fine, dusty sand revealed
并有了令人意外的发现
something quite unexpected.
尽管火星表面看起来完全干燥
Even though the surface of Mars appears completely dry,
但土壤中仍有2%的成分是水
2% of the soil is still made up of water.
“好奇”号♥发现的证据表明
Curiosity had found evidence of just how wet a planet
火星曾是一颗湿润的行星
ancient Mars had been.
数十亿年前
For hundreds of millions of years,
火星 40亿年前
火星曾是一个水世界
Mars was a water world.
这里雨水充沛
Rains fell,
河流奔腾
rivers ran,
而在北半球
and, in the northern hemisphere,
雨水汇聚成一个巨大海洋
water collected in a vast sea
覆盖了火星表面的五分之一
that covered a fifth of the Martian surface.
这颗红色行星曾经也呈现着蓝色
The Red Planet was once blue.
所有证据表明 约40亿年前
All the evidence suggests that there were large bodies
火星上曾存在大量的水