Here's How Space Megastructures Will Look, According to Neal Stephenson

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Famed scifi author Neal Stephenson’s new novel Seveneves is out today, and one of the most exciting things about it is that it’s packed with realistic representations of space megastructures where humans live. We talked to Stephenson about his ideas, and have some exclusive art from Weta showing what they look like.

Mild spoilers for the book follow.

The premise of Seveneves is in the novel’s very first sentence (you can read the first chapter on Gizmodo here):

The moon blew up without warning and for no apparent reason. It was waxing, only one day short of full. The time was 05:03:12 UTC. Later it would be designated A+0.0.0, or simply Zero.


After Day Zero, which happens about a decade into our future, humanity discovers that it only has a few hundred day left to live before fragments of the Moon start bombarding the planet and turn it into a fiery hellscape. So the world’s governments, engineers, and an Elon Musk-esque space entrepreneur get together to try to turn the International Space Station into the centerpiece of a massive “swarm” of spacecraft that will hold a couple thousand humans and keep them safe for the next 5,000 years while the Moon carpet-bombs Earth.

Above, you can see what eventually happens to the Endurance, one of the spacecraft launched in the frantic years before what the characters call the “hard rain” of Moon fragments. It’s been joined to the old space station, radiation shielded with a massive chunk of ice chipped off of a nearby asteroid, and it’s basically running for its life out of the burning Earth’s gravity well.


Stephenson told me by phone from Seattle:

I wanted to create an interesting scifi universe that didn’t violate the laws of physics, and that means that you’re limited to staying inside the solar system. I also wanted to get away from the ship-centric style of science fiction. Star Trek is ship-centric and it’s all about the Enterprise — there are many other examples. What if we decided to get away from the obsession with ships and instead thought about big machines and structures that might be used to create a civilization inside the solar system?


Above, you can see an illustration of the many kinds of craft that Earth launched to become the swarm that’s humanity’s new home. They need many small craft in order to make their habitat resilient and able to move fast — especially because they’re surrounded by the debris from the Moon exploding. So if a chunk of rock is hurtling toward them, the ships follow a complicated algorithm to spread apart and get out of the way.


At the core of the swarm is Izzy, the nickname for a future version of the ISS. Future asteroid miners have attached a metal-rich asteroid to her, and a roboticist aboard the craft is researching how to use her fleet of robots to mine it.

Because everybody is stuck in small groups in those “arklets” you see in the illustration above, they communicate mostly via the internet. And this results in a horrific social media war after humanity’s demise. I won’t spoil it for you, but suffice to say that when the last couple thousand people on Earth start trolling each other online, it gets really terrifying.


Stephenson says:

It’s common to observe that the style of discourse on social media doesn’t always represent what’s best in ourselves. So this is more of a contingent thing — it’s about having the wrong technology at the wrong time. Disastrous consequences emerge from it.


He also believes that space technology as we know it today was developed at the wrong time:

We developed space tech too early due to weird historical circumstances. Hitler wanted to bomb London so he put resources into rockets way ahead of they would have been built otherwise. Before the war they were just small experimental things. And then suddenly this bizarre situation came up where the only way that Hitler could bomb London was by building rockets. It wasn’t even a good military strategy, but he was crazy and had dictatorship so he got what he wanted.

So rockets are like this weird thing in tech history, and their development accelerated even more with A bomb being developed at the end of that war. Rockets were a great way to throw nukes around. So between Hitler and the U.S. and Soviets during the Cold War, a staggering amount of resources got thrown at rockets, over a span of a few decades. And all the smart people who work at Google today would have been building rockets back then.


The pendulum between information tech and space tech is swinging back the other direction, though. Stephenson adds:

In the last couple of decades, we’ve swung the other direction. We’ve dropped everything on the front of infrastructure and smart people are doing apps or what have you. It’s been two extreme swings of the pendulum. And now I think we’re coming back to reasonable middle ground. where Elon Musk — who made his fortune in information technology — is applying that money to building rockets.


In Seveneves, the offspring of the people who make it into space eventually figure out how to live there permanently. And they build massive cities out of the Moon’s debris, forming a ring of habitats around Earth. They travel between these cities by riding on “the Eye” (pictured above), which is a city in the shape of a wheel — and the cities of the ring pass through it, docking briefly so that people can get on and off. There’s actually a whole city built inside a chain on the inner ring of the Eye, which is called Chainhattan.


Stephenson said:

There’s been plenty of work for many decades about things like O’Neill [cylinders], built with in situ materials. I wanted to know — what if you made a machine that flew back and forth to connect each of these habitats in turn. There are certain parts of the world like the Philippines where everybody is on an island, so ferries become incredibly important. So then I started figuring out how you could make a device that would sit up there and have the ability to connect with different habitats at different times.


Plus, he wanted to connect the Eye with Earth. So he imagined a mobile space elevator hanging down from its outer ring, with a city called the Cradle serving as a counterweight in the atmosphere:

If you work on physics it requires a system of counterweights to traverse around the ring. It seemed to make sense to run a tether down to the surface and have a space elevator on the tether. It hangs lose in atmosphere and it’s effectively a city on the end of a rope. It gets dragged through clouds and it can be set down in certain locations.


There’s nothing better than reading about space megastructures that you want to visit. Well, visiting them would be even better. But for now, we can at least read Seveneves and feast our eyes on these incredible illustrations of the space cities of tomorrow.


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