alive. It looks like we'll only ever have small  crews spend a miserable time hidden underground.  

看來我們只會讓小團隊在地下度過一段悲慘的時光

Except, we could terraform it into a green  new world. But to solve the planet's problems,  

除非我們把它地球化成一個綠色新世界。但要解決這個星球的問題

we first need to make it worse and turn it  into oceans of lava with gigantic lasers.

我們首先需要把它弄得更糟，並用巨大雷射器將它變成熔岩海洋

This isn't a far-fetched science fiction tale.  Terraforming Mars is possible, on the kind of  

這並不是個牽強的科幻故事。地球化火星是有可能的

time scale our ancestors built great monuments  in. If humanity solves some of its pressing  

在我們祖先建造偉大紀念碑這種時間尺度上。如果人類解決了一些緊迫難題

problems and ventures into space to expand into  the solar system, this may not be that far off.

並為了擴張到太陽系而冒險進入外太空的話，這可能不是太遙遠的事

Ok. So how do we terraform Mars  quickly? Well, It's complicated.

好的，所以我們怎麼快速的地球化火星呢？這有點複雜

Mars is dry and has no soil to grow anything. Its  atmosphere is too thin to breathe or protect from  

火星乾燥且沒有能讓東西生長的土壤。它的大氣過於稀薄無法讓人呼吸或屏蔽

radiation, giving you a high risk of cancer.  So to turn it into a new home for humanity,  

輻射，使你患癌症的風險很高。所以想把它變成人類的新家

we have to give it a proper atmosphere, similar  to Earth's. It should be made of 21% oxygen,  

我們需給它一適當的、和地球相似的大氣。它應有百分之二十一氧氣

79% nitrogen and a tiny bit of CO2, at an average  temperature of 14°C and under 1 bar of pressure.

百分之七十九氮氣和一點點的二氧化碳，并有十四攝氏度的平均溫度以及低於一巴的氣壓

We have to create oceans and rivers and then the  ground has to be weathered into fertile soil to  

我們還要創造海洋與河流，且地面必須被天氣調養成肥沃的土壤

host living things. Then we need to install  a biosphere on the surface and prevent it all  

以供生物存活。之後我們需要在地表培養一生物圈，並安裝

from being undone by installing protective  measures that can stand the test of time.

一些能經得起時間考驗的防護措施以避免它被消滅

It's difficult. But a big  laser makes it a lot easier.

這挺難的，但有個巨大雷射器會讓事情簡單許多

Challenge 1: The Atmosphere

挑戰一：大氣層

Some 4 billion years ago Mars had a nice  oxygen-rich atmosphere and was home to vast  

約四十億年前火星有著氧氣充足的大氣層，並擁有寬廣的海洋與河流

oceans and rivers. It held onto it for  several hundred million years before it  

它持續擁有這些數億年

got blown away. Ultraviolet rays broke down  the atmospheric gases and then the oceans,  

直到被吹散為止。紫外線分解了大氣中的氣體，並分解了海洋

until they were swept away by solar wind.  Today Mars is a dry, barren wasteland.

直到它們全被太陽風吹走。如今的火星是個乾燥荒蕪的不毛之地

Luckily a sizable portion of the water is frozen  in deep reservoirs and in the polar ice caps,  

幸運的是有相當可觀數量的水被凍結在水庫深處及兩極冰蓋中

enough to create a very shallow ocean.  And enormous amounts of oxygen are bound  

足以創造一非常淺的海洋。此外，大量的氧氣以礦物質的

as minerals in the Martian rocks,  like the oxygen in the iron oxides  

形態束縛在火星岩石中，如讓火星呈現鏽紅色的

that give the planet its rust-red colour,  as well as carbon dioxide in carbonates.

氧化鐵以及碳酸鹽中的二氧化碳

To free these gases, we need to  reverse the reactions that lock  

要釋出這些氣體，我們需要

them away by using thermolysis,  which occurs at temperatures as  

通過使用如太陽表面高溫的熱分解來

high as on the surface of the Sun. In  short, we want to melt Mars' surface.

逆轉將它們束縛的反應。簡而言之，我們需要讓火星地表熔化

The best way to do that would be to put lasers  in orbit aiming their beams down on Mars.  

最好的方式是把雷射器發射到軌道並瞄準火星

The most powerful laser today is the ELI-NP,  

今天最強力的雷射器是ELI-NP

able to produce beams of 10 Petawatts  of power, for a trillionth second.

能夠放射出十拍瓦的射線，長達一萬億分之一秒

To melt Mars we need a laser twice as powerful,  that runs continuously. The easiest way is to use  

要熔化火星我們需要其兩倍威力且能持續放射的雷射器。最簡單的方法是使用

a solar-pumped laser that can be powered directly  with sunlight: At its core are metal-infused glass  

直接由太陽光供電的太陽光泵浦雷射器，其核心是灌了金屬的玻璃棒

rods that absorb energy and release it as a laser  beam. If we build an array of mirrors in space,  

能夠吸收能量並以雷射的形式釋放。如果我們在太空建造一鏡子陣列

about 11 times the size of the United States, we  can focus enough sunlight onto them to melt Mars.

大小約達十一個美國，我們能聚集足夠的陽光熔化火星

Let's do it!

動手吧！

As the lasers hit the surface, about 750  kg of oxygen and some carbon dioxide emerge  

隨著雷射擊中地表，約有七百五十公斤的氧氣和一些二氧化碳

from every cubic meter of rock melted. If  we are efficient our lasers only need to  

從每一立方米的熔化岩石中釋放出來。要是我們有效率

melt through the top 8 meters of  the surface to get enough oxygen.

我們只需熔化地表頂部八米來得到足夠的氧氣

It would look terrifying. The  skies would be shrouded in storms,  

場面會很嚇人。天空會被雷雲籠罩

while the ground would glow red-hot,  criss-crossed by currents of lava.  

地面會熱的通紅並充滿了縱橫交錯的熔岩流

Tireless laser beams sweep over the landscape,  leaving trails too bright to look at. After they  

雷射光束毫無倦怠的掃過景觀，留下耀眼的痕跡讓人無法直視。它們

pass, the ground cools quickly. A strange  snow falls: the ashes from all the elements  

經過之後地面迅速冷卻。天空開始下一場奇怪的雪：元素如硅和鐵

that solidify as they cool down, like silicon and  iron. Mars is still a cold planet at this point.

隨著溫度冷卻而固化形成的灰燼從天而降。火星到這階段仍是個寒冷的星球

A happy side effect of this inferno is that  all the water in the polar ice caps and even  

這個煉獄有個讓人高興的副作用：兩極冰蓋甚至

deep underground rises into the sky as hot  steam, forming clouds that rain down over  

地下深處的水以熱蒸氣的形式升到空中，形成雲朵降雨沖洗

the entire planet. They would wash out  the nastier gases from the atmosphere,  

整個星球。它們會清除大氣中那些較討厭的氣體如氯氣

like chlorine, and carry away harmful elements  that accumulated on the surface. In the end, they  

並帶走堆積在地表的有害元素。到最後

would form shallow oceans, saltier than on Earth.  We might need to do an extra clean-up afterwards.

它們會形成比地球海洋還要鹹的淺海。我們隨後可能需要再額外清理

It would take about 50 years of continuous  lasering to create our oxygen atmosphere. We  

我們需要約五十年的持續放射來創造我們的含氧大氣

could use this opportunity to dig deeper in some  places to create the basins for salty oceans or  

我們可以借此機會在某些地方挖深一點，以製造鹹海盆地或

rivers and spare some landmark features  like Mons Olympus and Valles Marineris.

河流，並保留一些地標如奧林帕斯山和水手號峽谷

We're not done though.

但工作還未結束

The resulting atmosphere is nearly 100%  oxygen and only 0.2 bar. It's hard to  

產生的大氣幾乎全是氧氣且只有零點二巴，讓人難以

breathe and very flammable. To make  it similar to earth and a lot safer,  

呼吸而且空氣非常易燃。為了讓它更接近地球且更安全

we need to add a lot of nitrogen, which  Mars is lacking sadly. We have to import it.

我們需要加入大量的氮氣。可惜火星缺乏氮氣所以我們必須引進這氣體

The ideal source is Titan, a large moon of Saturn,  covered in a thick atmosphere that's almost  

理想的來源是土星的巨大衛星泰坦，其濃厚的大氣幾乎

entirely nitrogen. We just have to move 3000  trillion tons from the outer solar system to Mars.

全是氮氣。我們只需從太陽系外圍搬運三千萬億噸的氮氣到火星上

While that's not easy, it is doable. To  process that much of Titan's atmosphere,  

任務雖然不簡單但可行。要處理這麼多的泰坦大氣

we have to construct giant automated factories,  on its surface powered by our lasers to suck in  

我們需要在其地表建造由雷射器供能的巨大自動化工廠

the atmosphere and compress it into a liquid.  This gets pumped into bullet-shaped tanks,  

以吸入大氣並把它們壓縮成液體。這些液體被泵入子彈形的容器後

which a mass driver shoots all the way to  the red planet, where they explode and mix  

將由質量投射器射回火星並在撞擊時爆炸

with the oxygen. We've already been able to send  individual missions to Saturn in just a few years.  

與氧氣混合。我們已能在短短幾年內把單獨任務發射到土星去

With enough resources, it should be possible  to complete the task within 2 generations. 

只要資源足夠，我們應能在兩世代內完成任務

Of course it would be much more  convenient to have nitrogen left  

當然的，如果在地球化金星時有多餘的氮氣可用那就更方便了

over from terraforming Venus on the side: we  explained this in detail in another video.

我們在另一部視頻裡仔細解釋了這個過程

So, about a century after the  start of the terraforming process,  

地球化開始大概一世紀以後

we have a breathable atmosphere that has  the right gases. If the liberated CO2  

我們創造了可呼吸的、擁有正確氣體的大氣

isn't enough to warm it up to temperatures we  can stand, we just add some super greenhouse  

如果釋出的二氧化碳不足以加熱到我們可承受的溫度，我們只需加些溫室氣體即可

gases. Mars at this point resembles a  black marble from all the cooling lava,  

火星在這階段因冷卻的熔岩像個黑色大理石

spotted with growing oceans and red patches  where the old surface remains untouched. It's  

並有著增長中的海洋斑點，以及沒被改變的紅色舊地表斑塊

still a wasteland, no better than a desert  on Earth. We need to fill it with life.

它仍一片荒蕪，不比地球的沙漠好。我們需要賦予它生命

Challenge 2: Biosphere

挑戰二：生物圈

Installing a biosphere on a new planet is  very difficult. Unexpected interactions  

在一個新星球培養生物圈非常困難

between species or sudden diseases can  destabilise it to the point of collapse.

意想不到的物種間互動或突發疾病可以使之不穩定到崩潰的地步

We would probably begin by seeding our young  oceans with phytoplankton. Without competition,  

我們或許從在年輕海洋播種浮游植物開始

it would bloom rapidly, filling up the oceans  to become the bottom of an aquatic food chain.  

在沒有競爭者的情況下，這些植物會迅速盛開，填滿整片海洋成為水生食物鏈的底層

They can be followed by tiny zooplankton,  

之後我們可以加入浮游動物，隨後是魚類

then by fish. Maybe even sharks and whales. If  things go well, life in the oceans will thrive.

甚至可能鯊魚和鯨魚。如果培養順利，海洋生命會很繁榮

Life on land is harder. Plants need  nutrient-filled ground to sink their roots  

陸地上的生命較難培養。植物需要充滿養分的地面來紮根

into. But most of the surface is the congealed  remains of lava and ashes. We could wait for  

但火星表面大部分佈滿了熔岩和灰燼的凝固殘骸

thousands of years for water and wind to grind it  down into finer sands or try to do it manually.

我們可以等個幾千年讓水和風慢慢把它們磨成更細的沙，或我們可以自己磨

But we want to be quick. And we have a  big laser. Turning the beam on and off  

但我們想要更快，而且我們還有個大雷射器

in rapid succession would cause the ground to  quickly heat up and contract, which breaks it  

迅速地開關雷射器能使地面很快的升溫又收縮，導致它碎裂

into smaller and smaller pieces. Add a bit  of water, and you get a sort of dark mud.

成小塊。加一點水，你就得到一種黑泥

Into this mud, we can mix fungi and  nitrogen-fixing bacteria. They're  

在這泥漿裡，我們可以混入真菌與固氮細菌

able to absorb nitrogen and convert it  into nitrate compounds to feed plants.  

它們能夠吸收氮氣並將之轉化為硝酸鹽化合物，當作植物的養分

The first plants we want to bring are  native to volcanic islands on Earth,  

我們想要帶來的第一批植物源自於地球上的火山島

since they are perfectly suited to  the laser-blasted Martian landscape.

因為它們很適合這個被雷射爆破的火星景觀

Eventually, the enriched mud becomes the  foundation for grasslands and forests. In  

到最後，這些肥沃的泥漿將成為草原與森林的根基

Mars' lower gravity, trees can become very tall  very fast. Their roots gather the nutrients  

在火星較弱的引力下，樹木能在短時間內長得非常高。它們的根聚集了

they need and then dig deeper to turn more rocks  into soil, forming a self-sustaining ecosystem.

所需的養分並更深入的挖掘把岩石化為泥土，形成一自維持的生態系統

At this point we can slowly introduce more plant  varieties, insects and animals. Not mosquitoes  

到了這步我們可以慢慢引進更多種的植物、昆蟲及動物，但不要有蚊子

though. The new biosphere needs to be maintained  to prevent it from falling out of balance. If  

嶄新的生物圈必須小心維持以免失衡

plants grow too quickly and absorb too much  carbon dioxide, the planet cools down too much.  

如果植物生長得太快並吸收太多的二氧化碳，火星將過度冷卻

If key species die out, we could see populations  collapse faster than they could recover. On Earth,  

如果某關鍵物種滅絕，種群可能會快速崩潰來不及復原

other species would move in to fill the void,  but our Martian biosphere is not as flexible.

在地球上，其他物種能替代填補空缺，但我們的火星生物圈沒那麼有彈性

It takes hundreds if not thousands of years  before Mars becomes a stable environment.

火星要花上數百年甚至數千年的時間才能變成穩定的環境

But eventually the planet will have the potential  to sustain large human colonies. With air,  

但最後這個星球將有潛力支持龐大的人類群落

water and food available, we  can finally call Mars – black,  

有了空氣、水以及食物，我們終於可以稱火星這個

blue and green – our home. A  giant, volcanic island in space.

又黑又藍又綠的星球為家了。一個在太空的巨大火山島嶼

Will it last though?

但這能永久維持嗎？

Challenge 3: The long-term future

挑戰三：長遠未來

There is a problem we haven't addressed: Mars'  core does not produce a magnetic field, so it does  

還有個問題尚未解決：火星的核心並不會產生磁場，因此無法

not have enough protection from solar radiation  or cosmic rays. This becomes dangerous for the  

對太陽輻射或宇宙射線做足夠的防護。這會對火星居民

long term health of Martian populations. So as a  final step, we need an artificial magnetic field.

的長期健康帶來危害。所以作為最後一步，我們需要個人造磁場

It doesn't have to be huge like Earth's. It  

它不需要像地球的這麼大

just needs to deflect the solar wind  enough so that it doesn't touch Mars.

只要能使太陽風偏離火星就夠了

The easiest way is to construct a magnetic  umbrella far ahead of Mars that splashes the solar  

最容易的方法是在火星前方遠處建個磁性雨傘，以遮擋

wind to the sides. A big, superconducting ring  powered by nuclear facilities is all it takes.  

太陽風。我們只需要一個由核設施驅動的大型超導環就行

It would orbit at the Mars-Sun L1  point, keeping it constantly in  

它會在日火L1平動點環繞，固定在

between the Sun and Mars and protect  the new atmosphere. And that's it!

太陽與火星之間保護著新大氣，這樣一來就大功告成了！

Terraforming Mars would take some work,  hefty resources and probably a century or  

地球化火星需要花費些精力、龐大的資源及一或十世紀的時間

ten but it would be the first time  we've lived in a home designed and  

但這會是我們第一次居住在一個由我們設計、為我們打造的家園

shaped solely by us and for us. A first  step towards our future among the stars.

這也是邁向星際未來的第一步

The first step we can already take  down on Earth is learning more about  

我們已經可以在地球上採取的第一步是學習更多

the physics and biology needed for such a project.

這類項目所需的物理及生物知識

To help you with that, we've created a series of  lessons to build your fundamental understanding  

為了幫助你學習，我們創建了一系列課程來加深你對這些

of these topics. Made in collaboration  with our friends at Brilliant.org,  

主題的基本理解。這些和在Brilliant的朋友們

these lessons give you a deeper understanding  of the topics from our most popular videos,  

合力製作的課程讓你深入了解我們熱門視頻的主題

from supervolcanoes to black  holes to climate science.

從超級火山、黑洞到氣候科學等等

Brilliant is an interactive learning tool  that makes math, science, and computer  

Brilliant是個通過動手的方法使數學、科學及電腦

science accessible with a hands-on approach.  Because we know that to really learn something,  

科學變得容易的互動學習平台。因為我們知道要真正學習某事物

you've got to do it. Think of each lesson as a  one-on-one tutoring version of a Kurzgesagt video.

你必須自己動手做。把每個課程當作是一對一的指導版Kurzgesagt視頻

In our latest lesson, you'll learn more  about how Mars lost its atmosphere and  

在我們最新的課程裡，你將學習有關火星如何失去大氣層

how we might protect a terraformed  Mars from suffering the same fate.

以及如何確保地球化的火星不再遭受同樣命運的知識

Brilliant has thousands of lessons to explore—from  math-based topics like algebra and probability  

Brilliant有上千堂課程供你探索，從數學方面的課題如代數和概率

to the concepts behind algorithms and machine  learning. And with new lessons added each month,  

到演算法和機器學習背後的概念等。隨著每個月包括Kurzgesagt在内的

including ones from Kurzgesagt, you'll  always find something fascinating to learn.

新課程發布，你總能找到一些有趣的東西來學習

To get hands-on with Kurzgesagt lessons and  explore everything Brilliant has to offer,  

想動手學習Kurzgesagt的課程並發掘所有Brilliant能提供的知識

go to Brilliant.org/nutshell  and sign up for free today.  

今天就上Brilliant.org/nutshell免費註冊

There's even an extra perk for Kurzgesagt  viewers: the first 200 people to use the link  

Kurzgesagt觀眾更能享受特殊優惠：首兩百位使用這個連結

get 20% off their annual membership, which  unlocks all of Brilliant's courses in math,  

的人享有百分之二十的年度会員費折扣，並解鎖Brilliant所有在數學

science, and computer science. We love seeking new horizons with our  

科學及電腦科學的課程。我們熱愛在研究上追尋新視野

research – Brilliant will be the catalyst  to expand the limits of your knowledge.

Brilliant將會是擴大你的知識邊界的催化劑