Making the Impossible Possible: The Hard Tech Behind the Moon Landing

Hi everyone, welcome to Cold-Knowledge Blind Box. I'm your community host, Qiao Yulan. This episode features a car owner from Foshan, @..., who is filling in for my voice.

When you looked up at the stars as a child, did you ever imagine that one day, space travel would be as easy as a business trip across the city, as if in a science-fiction movie?

Then we grew up. We got busy with school and jobs. Even finding a place where we can clearly see the Milky Way is hard.

So in this episode of Cold-Knowledge Blind Box, we'll refocus our attention on the sky. Split into two parts, we'll revisit the interesting stories behind humanity's first trip to the Moon, as well as the promising Mars program ahead.

Let's turn our gaze to these plans that seem impossible, and see what solutions scientists and experts of all kinds came up with to face the unprecedented technical challenge of landing on the Moon. From a god's-eye view, let's re-examine these incredible ideas, see what inspiration they hold, and feel the courage and praise that humanity has to offer.

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

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

What? That's not even a question of how it was done anymore. It's a question of how it could possibly be done at all. All because President Kennedy boasted to Congress in 1961 that we would land on the Moon within 10 years?

No one was more shocked than the scientists and engineers at NASA. It meant that in less than ten years, they had to invent a lunar spacecraft.

At the time, no one knew how to get into lunar orbit. No one knew how big a rocket would be needed. No one knew how small and how powerful a computer would have to be. No one knew what the surface of the Moon was like. No one knew what astronauts would eat on the Moon.

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

For example, the whole Moon mission must use computers, right? And it must carry out enormous amounts of tightly precise mathematical calculations, right?

Astronauts have to wear clothes on the Moon, right? These suits must be radiation-resistant, protect against cosmic particles, and keep the wearer warm. On top of that, you have to make sure the person inside this suit, which is as heavy as full body armor, can bounce around on the Moon without tearing it open.

Once people are sent into space, we at least have to make sure we don't lose contact, right? And ideally, there should even be a live broadcast! Never mind back then, even today, maintaining a continuous connection with satellites is not 100 percent achievable.

Yes, this was the 1960s. Only about twenty years had passed since the first computer was built. Most computers still looked much as they did when they were first invented, and they still took up half a room. What they could do was limited to simple mathematical tasks. Personal microcomputers wouldn't appear until 1971.

Even though it's a big machine, the memory unit, the most important part for computing, usually had only a few kilobytes. Did you want to pack these computers together and launch them into space? Don't even think about it.

Even the internet wouldn't appear until after the Moon landing succeeded, and using optical signals for nearly instantaneous information transfer would have to wait until the 1980s. And that's only the auxiliary hardcore technology. As for the technology that astronauts would use directly, even the design and protection of the spacesuit was a huge challenge for the materials science of that time.

Yes, the Moon landing itself involved 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." (Who knows, the smart chips built into a modern household washing machine may have far more computing power than the Apollo lunar module.) Even if you traveled back to that era, no matter how optimistic and confident you were, you would have a hard time believing that humanity could complete a Moon landing in such a short time.

So much so that many people have always thought the American government had director Stanley Kubrick film it in a studio.

If anyone wanted the American Moon program to be fake, it would have been the Soviet Union. Even the mighty KGB couldn't disprove the Moon landing. Astronauts even left a laser ranging retroreflector and a seismometer on the Moon. Surely no one still thinks the Moon landing was... fake?

So how did the engineers and scientists achieve the impossible, beyond their era? The answer may be surprising, but yes: they relied on the old-fashioned method. With no advanced technology, they used a sea of people! In an era without artificial intelligence, they achieved intelligence by human hands!

Take the core of the entire plan, the Moon landing computer. The Apollo spacecraft had two computers. One was responsible for taking the command module from Earth to the Moon and back. The other was responsible for calculating the round trip between lunar orbit and the lunar surface for the lunar module.

Yes, the brilliant people at MIT managed to build the smallest, fastest and most flexible computer of that era. Compared with the ordinary computers that took up half a room, the computer on the Apollo spacecraft was only the size of a briefcase, used to help astronauts with navigation.

Back then, computers on Earth had to be fed punched cards to run, and results often took hours to come out. It was like clicking a calculate button on your phone and then waiting hours for the answer.

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

Only absolute precision could ensure that programs 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 the 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 carry out binary operations.

Weaving computers was very dull work, but it required skill, experience, and enough focus.

It's said that the female workers at the factory once staged a brief strike. To keep up with the schedule, the factory manager and foreman sat down and wove themselves, but what they wove turned out to be defective...

Truly, one hour of spaceflight required a million hours of effort from people on Earth.

Apart from weaving computers, textile workers also had to weave the parachutes for the lunar return capsule.

The cloth for these parachutes had to be strong enough to withstand the extremely fast descent of the return capsule, yet light enough. Because even a tiny bit of extra weight could push the lunar module over its weight limit, causing it to miss the proper return trajectory.

Each parachute was made by stitching together pieces of cloth, and one parachute would have 2 million needle holes. Workers stitched every single one by hand on old-fashioned sewing machines. A single wrong stitch could lead to catastrophic consequences.

Finally, these parachutes were folded by workers. During the Apollo missions in the 1960s and 1970s, only three people in the whole United States were certified to fold parachutes for Apollo spacecraft.

Because these three were so incredibly important, NASA forbade them from riding in the same car, in case a car accident killed all of them at once... They really couldn't afford such an accident...

Apart from the computers and the parachutes, NASA also sent three electric vehicles to the Moon. Because there is no oxygen in space, the internal combustion engines of gasoline cars would simply stall. I wonder when the first NIO car will be able to fly beyond the atmosphere?

There are still many, many more hardcore technologies related to the Moon landing. The one thing that never changes is humanity's courage and praise in the face of difficulty. Even a plan that seems impossible can, through sound planning and collaboration, bring unexpected technological progress. You could say that without the Moon program, the arrival of many modern conveniences would have been delayed.

Alright, the hardcore technology behind the Moon landing ends here. If you have any other cold-knowledge topics you'd like to hear, you can also open the NIO app, go to the Friends screen, find the community NIO Radio Shenzhen city branch, and share the cold knowledge you like together.

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