Making the Impossible Possible: The Plan to Move to Mars

Hi everyone, welcome to Cold-Knowledge Blind Box. I'm your host, Qiao Yulan.

Last episode we talked about how, in the 1960s, when computer memory was still only a few kilobytes, humans still managed to pull off the seemingly impossible Moon landing. So today, with all the powerful technology we have and the fast-moving progress in artificial intelligence, could we witness humans immigrating to Mars in our own lifetimes?

This episode we'll talk about the plan to move to Mars. Let your imagination run free, and enjoy the future the way you did as a kid. Let's look at what it would take to reach this enormous goal, and what the right direction would be to actually make it happen.

Wait, hold on. Why must we go to Mars at all? The simplest reason is that you shouldn't put all your eggs in one basket. If every species on Earth went extinct, a backup base on Mars could help carry Earth's species forward.

So why does Mars come to mind first whenever space migration is discussed? Apart from the Sun, can't we reach any other planet in the solar system? Well, it's true, we can't. First, the planet we move to has to be habitable. That means it can't be too close to the Sun, or it would be scorching hot, and it can't be too far from the Sun, or it would be freezing.

Earth's position is just right, neither too far nor too close. The two planets closest to us are Venus and Mars. Venus has a harsh environment: its air pressure is 92 times that of Earth, its atmosphere is almost entirely carbon dioxide, and it is covered in clouds of dilute sulfuric acid. Its surface temperature stays at around 460 degrees Celsius all year round. Even landing a probe there is extremely hard, and life certainly couldn't survive.

By comparison, Mars's basic conditions are much better. Mars looks red because its surface is made mostly of iron oxide rock, which is very similar to basalt on Earth.

Mars's gravity is about 38 percent of Earth's, and one rotation takes 24.3 hours, which matches the day and night rhythm that humans and most life on Earth are used to. And Mars's axis is tilted a little, so Mars has seasons too, though each season lasts about two years. Put simply, one year is summer and the next is winter.

But Mars's atmosphere is extremely thin. Its air pressure is only one percent of Earth's, and it has no oxygen. This means Mars effectively has no atmosphere to block cosmic rays from outer space, and the ultraviolet light is very strong. The temperature also swings wildly between day and night. On the Martian equator, it can drop to minus 70 degrees at night and climb back to 20 degrees during the day.

And even at its closest approach, Mars is still 55 million kilometers away from Earth. Sending astronauts there takes at least six months, unlike a trip to the Moon, which takes only 8 days and 3 hours. So if we simply sent people to Mars to go around for a day, take a photo, and fly back, the journey would be more symbolic than practical.

If humans really land on Mars, we should do what we did when we built the Antarctic research stations: set up a permanent settlement on Mars in advance. Then, when the next group arrives, the two teams can rotate. That is the more sensible way to explore Mars.

So the first step of the Mars immigration plan has to be transforming Mars's atmosphere. At the very least, we should first build houses on Mars and try growing plants indoors. Mars has carbon dioxide and ultraviolet light, which is enough for plants to photosynthesize. That way, the forward base can first be filled with oxygen.

So the first step is to send all kinds of robots over. Based on this idea, NASA launched a challenge in 2015: use 3D printing technology to build houses out of basalt, which means using local Martian materials for construction. After all, dropping bricks from Earth to build houses there would be far too extravagant.

After a four-year competition, a company called AI Space Factory took the crown. Its technology can turn basalt into a liquid that behaves like cement, and then, just like stacking Lego bricks, it builds up layer by layer until a house is printed on Mars.

Once there are plenty of oxygen-filled houses, humans can gradually send all kinds of seeds, eggs, or fertilized eggs to Mars, and officially begin trying to nurture life there.

But this approach can only sustain a small number of people, basically a few research scientists. If we want large-scale interplanetary migration, we'll have to thoroughly transform Mars's environment, for example by rebuilding its atmosphere.

As a passionate fan of Mars migration, when someone asked Musk how we could thoroughly transform Mars's atmosphere, he threw out a startling idea: why not just use nuclear bombs on Mars's north and south poles to turn the ice layers directly into water vapor? There is also dry ice in those regions, which is solid carbon dioxide. Once a large amount of carbon dioxide is released into the atmosphere, it could form an atmosphere on Mars. With water vapor, rain and rivers on Mars would not be hard to achieve.

But some people reject this crazy idea, saying that even if all the ice melted, it would only raise Mars's atmospheric density from the equivalent of 1 percent of Earth's to 1.6 percent. "If you're going to use nuclear bombs carelessly like that, you might as well put a huge number of solar panels along Mars's equator. They can generate electricity, and they can also reflect the Sun's direct rays to heat Mars, which would raise the planet's own temperature and gradually create its own greenhouse effect."

However, all these ecological transformation plans would take hundreds of years of sustained investment before the climate on Mars could gradually change. So the Mars migration plan is, to a large extent, a plan to transform an entire planet. People believe that plans to transform a planet's environment are feasible because, when Earth first formed, its climate conditions were very similar to Mars's. By chance, with the appearance of the most primitive life, bacteria, Earth's atmosphere began to change gradually, and eventually took on the form it has today.

So this is actually very similar to the myth of Pangu splitting the sky and earth, and then Nüwa creating humans. First the environment of the heavens and earth has to be made right, a good environment that can nurture life has to be cultivated, and only then do humans appear. So the realization of the interplanetary migration dream may well depend, to a large extent, on the level of human agriculture! And that's a natural talent of us Chinese people!

Alright, our wild imagining of Mars migration ends here. If you have any other cold facts you'd like to hear, you can open the NIO app, go to the friends screen, find the community called NIO Radio Shenzhen City Branch, and share the cold facts you like with us.

How far we can go depends largely on how far that planet is from Earth. Time is the most terrifying resource. At the speed and power of today's spacecraft, we...

Current chemical-fuel spacecraft

How far we can go really depends largely on how far that planet is from Earth.

As for who most wants to go to Mars, it has to be someone other than Musk.

Crazy plans. When we gaze at the stars, under the grand goal of landing on Mars, what inspiration do they bring to our thinking?

Let's turn our attention to these seemingly impossible plans and see what solutions scientists and experts of all kinds came up with to face the Moon landing, a technical challenge unlike any before. Looking at these incredible ideas from a god's-eye view, what thinking inspiration lies behind them, and feel the courage and the songs of praise that belong to humanity.

Those who reach for the stars must also be wrapped in ten thousand rays of light.

More than half a century has passed since humanity first landed on the Moon. It's said that on July 21, 1968, the day of the Moon landing, more than 650 million people around the world watched the live broadcast on TV. You could say that at that moment, almost every TV in the world was tuned to NASA's Moon channel. Even the crime rate that day dropped noticeably. And from the project's start to the first crewed Moon landing, this extraordinary historical moment took only seven years.

What? This isn't a question of how they did it anymore. It's a question of how they could possibly do it! Was it simply because President Kennedy boasted to Congress in 1961 that the United States would land a man on the Moon within 10 years?

NASA's scientists and engineers were stunned. It meant they had to invent a Moon-landing spacecraft in less than ten years.

And back then, no one knew how to get to the Moon. No one knew how big a rocket it would take. No one knew how small and powerful a computer would be needed. No one knew what the surface of the Moon looked like, and no one knew what astronauts would eat once they got there.

Let me list a few hopeless problems so you can see how hard this engineering challenge was.

For example, the whole Moon-landing process must use computers, right? It needs a huge amount of precise mathematical calculation, right?

Astronauts have to wear spacesuits, right? These suits must be radiation-proof, protect against cosmic particles, and keep the wearer warm. On top of that, you have to make sure the person wearing a suit that's practically full-body armor can still hop around on the Moon without the suit splitting open!

Once a person is sent into space, you at least have to make sure they don't lose contact, right? And ideally, you'd even provide a live broadcast! Never mind that era. Even today, keeping a continuous connection with a satellite is not something that can be guaranteed 100 percent.

Yes, that was the 1960s. Only about twenty years had passed since the first computer was built. Most computers were still almost the same as when they were first invented, still taking up half a room. All they could do was perform simple math tasks. Personal computers, the kind we commonly use today, wouldn't appear until 1971.

Though it's a big machine, its most important memory unit during calculations usually had only a pitiful few kilobytes. Want to pack those computers up and launch them into space? Don't even think about it.

Even the internet didn't appear until after the Moon landing succeeded, and near-instant information transmission using light signals wouldn't come until the 1980s. And those are just the potentially helpful hardcore technologies. As for technology that could be used directly by astronauts, even the design and protection of spacesuits was a huge challenge for the materials science of the time.

Yes, the Moon landing itself had far too many difficulties that went beyond the era. In the words of the Americans themselves, it was like driving a washing machine across the Pacific Ocean. (Honestly, the built-in smart chip in a modern household washing machine probably has much more computing power than the Apollo lunar module.) Even if you went back in time to that era, no matter how optimistic and confident you were, you would find it very hard to believe that humanity could complete a Moon landing in such a short time.

For this reason, there have long been people who think the whole thing was filmed in a studio by the American government with the great director Kubrick.

Who would most want the American Moon landing to be fake? It has to be the former Soviet Union. Even the mighty KGB couldn't disprove the Moon landing. And the astronauts even left a laser ranging reflector and a seismometer on the Moon. Surely nobody still thinks the Moon landing was... ah... fake?

So then, how did engineers and scientists manage to transcend their era and make the impossible happen? The answer may be surprising, and yes, it's the old method: with no advanced technology, fall back on massed manpower! In an age without artificial intelligence, rely on humans to make intelligence happen!

Take the core Moon-landing computer, for example. The Apollo spacecraft had two computers. One handled taking the command module from Earth to the Moon and back. The other handled calculating the lunar module's trips between lunar orbit and the Moon's surface.

Yes, the geniuses at MIT succeeded in building the smallest, fastest, and most flexible computer of that era. Compared with the ordinary computers that took up half a room, the Apollo computer was only the size of a briefcase, and it was used to help astronauts navigate.

Back then, computers on Earth needed punch cards to run, and results often took hours to come out. It was like clicking a calculate button on your phone and then having to wait hours for the answer.

But the Apollo computer had a keyboard, and it responded immediately. That came down to its unique design. Its memory was core rope memory, which was the densest computer memory of the time. It had to be woven by experienced female textile workers, who threaded the wires through designated positions with needles. Every single wire had to be perfectly precise. Yes, just like knitting a sweater: a wire passing through a magnetic ring represented 1, and a wire passing outside the ring represented 0.

Only absolute precision could ensure the program ran properly. Behind the Apollo Moon landing, there were truly many great, ordinary, and overlooked women.

If you've read The Three-Body Problem, the idea of a human-array computer shares the same principle as this "woven memory." Both can be called "semiconductors." Because what a semiconductor chip does is essentially process countless 0s and 1s to perform binary operations.

Weaving computers was extremely tedious work, but it required skill, experience, and a great deal of focus.

It's said that the female workers at the factory once staged a brief strike. The factory manager and the foreman, to keep the schedule on track, sat down and did the weaving themselves, and what they wove turned out to be scrap...

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