Nautilus Members enjoy an ad-free experience. or Join now .

World building is the best part of writing,” Andy Weir tells me. The software engineer turned writer is getting his practice in. In his 2011 novel The Martian, he built a Mars base, complete with carefully calculated Earth-Mars rocket schedules and chemistry-hacked potato farming. It was made into a 2015 hit movie grossing over $600 million (“I live in a bigger house now,” he tells me).

We get to see Weir’s newest creation this month with the release of his new novel, Artemis. The action is set on a lunar city in the not-too-distant future, which Weir calculated as much as imagined. He estimated the cost of reaching the moon from Earth by assuming a future commercial launch industry that will reach the efficiencies of today’s airlines, then combining those numbers with an obscure and complex Earth-moon orbit called the Uphoff-Crouch Cycler. He wrote a 10-page economic analysis constructing the future lunar economy, whose currency, the slug, is based on the cost of transporting one gram from the Earth. He referenced modern-day nuclear power plant designs in determining the base’s energy production and consumption budget.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

“The total time that passed by while I was working on Artemis, just the city, was like a year,” Weir says, “although not all of that year was spent working on it.” During our conversation, I needed to remind myself that he is a novelist, and not a scientist designing an actual base. Still, his message is clear and convincing: that a lunar base should be built before any other off Earth, and that doing so is getting surprisingly close to feasibility.

Fit and finish: A 1990 NASA sketch of a modular lunar outpost whose hardware focuses on crew health.NASA
Nautilus Members enjoy an ad-free experience. Log in or Join now .

Why should we colonize the moon before we colonize Mars?

I don’t think people understand the magnitude of difference there is between Mars’ distance and Earth’s distance. If you were on a football field, and you’re standing on one goal line and imagine Mars is on the other goal line, then the moon would be about four inches in front of you. Colonizing Mars before colonizing the moon would be like if the ancient Britons colonized North America before they colonized Wales. It would be easier to build a city on the moon for the sole purpose of assisting you in colonizing Mars than it would be to go straight to Mars.

In your book, what drives the colonization of the moon?

Before you colonize something there’s got to be economic reasons. In Artemis it’s tourism. The whole story is based on the presumption that the commercial space industry drives the price of traveling to the moon low enough for middle class people to afford it. Then it becomes economically viable to build a resort on the moon that people can go to. That’s sort of a once in a lifetime thing to do, and a lot of people would do that. The city of Artemis is built very close to the Apollo landing site so you can go there and look at it, you can do EVAs (extravehicular activity, or spacewalks) in little hamster balls, and it seems like it would be a pretty fun place to visit.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

The facilities for tourists to stay on during their trip to the moon only ever need to be thrown into orbit once.

What do you think the cost of travel to the moon will be?

In the story, the price of putting a human into low Earth orbit is $7,000 dollars in 2015 dollars, or $35 for a kilogram of freight. By comparison today’s price is around $4,000 for a kilogram of freight. Reaching low-Earth orbit is the hardest part of the journey. I got to these numbers by making a comparison to commercial aviation. Let’s say the commercial space industry and airline industry spent the same percentage of their revenue on consumables like fuel. After a bunch of research, I found that airlines spend about 16.5 percent of their revenue on fuel. Since I know the cost of rocket fuel, I can get total launch costs. There’s a lot of assumptions in there but it’s not completely out of the question, and it only has to be good enough for fiction.

What is the Uphoff-Crouch Cycler and how does it help tourists reach the moon?

Nautilus Members enjoy an ad-free experience. Log in or Join now .

The cycler is like a hotel that, once you put it into its orbit, doesn’t ever need to use fuel again. It just naturally stays in that orbit and goes back and forth between the Earth and the moon. You still need to accelerate your cargo up to the speed of the cycler itself to make a rendezvous. But the facilities for, say, tourists to stay on during their trip to the moon only ever need to be thrown into orbit once. There would be people who just live and work on the cycler. This is better than using one ship that goes directly back and forth between the Earth and the moon, which would require you to accelerate the humans and the ship every time. No one has ever made an Uphoff-Crouch cycler, but the orbital dynamics are sound and it is the cheapest way to make moon travel happen.

The currency of Artemis is the slug. What is a slug and how does it work?

One slug is the cost of transporting one gram of stuff from the Earth to the moon. I’m going to skip over the 10 pages of economic analysis I did while setting up for the book, but basically the exchange rate is six slugs to one 2015 dollar. So imagine you want to buy an iPhone. Okay, well an iPhone costs $1,000 so that would cost 6,000 slugs. But then you also need to get it shipped to the moon. Fortunately an iPhone only weighs about 100 grams, so that only costs you an additional 100 slugs. The total cost is $6100 slugs. Now instead let’s say you want to buy a nice couch for $500, or 3,000 slugs. But it also weighs 50 kilograms, so that’s 50,000 slugs to get it shipped to the moon. So you see mass matters a lot in how much something ends up costing in Artemis.

How is Artemis powered?

Nautilus Members enjoy an ad-free experience. Log in or Join now .

The first things that were brought to the moon from Earth were two nuclear reactors because they needed that energy to sculpt the aluminum to build the rest of the city. Nuclear power is incredibly efficient. You’ve got two nuclear reactors that can power an entire city but the actual nuclear fuel is kilograms of mass. The reactors themselves weigh 15 metric tons each and they’re based on the Gen4 reactor which is a real thing that exists now. They produce 27 megawatts each.

How does Artemis get water?

Artemis has plenty of oxygen as a byproduct of aluminum smelting done on the moon. To make water, the city imports hydrogen from Earth and then reacts it with local oxygen. For every kilogram of hydrogen they bring from Earth they can make nine kilograms of water, so the total cost is around 1,000 slugs. Water is also not a consumed resource. It’s a closed loop system. People consume water and destroy it, reuse it and give it back. Every ounce of water you consume leaves your body one way or another, either through sweat or through your breath or through your urine. All the city has to do is keep the water in the system. It purifies it and gets it back. So when you take a shower on Artemis what you’re really paying for is water purification. It’s not like buying food to put in your grocery store, it’s more like buying an airplane for your airline. Once you’ve bought it you can just keep using it.

What about food?

Nautilus Members enjoy an ad-free experience. Log in or Join now .

Artemis brings in a lot of its food from the Earth. It also mass produces food locally by growing algae. It doesn’t grow crops. Bringing over seeds is not expensive but it takes a lot of land area to grow crops. The amount of farmland necessary to support just one person is very large. On the other hand you just need a vat and a small room to grow as much chlorella as you want. You provide it with artificial light, and Artemis has as much energy as they want from their two nuclear reactors. It’s easy to give the algae constant light day and night so that it’s always growing.

I think I’m just going to stay on the moon for a while.

What’s at stake in the story?

The thing with science fiction that I’ve always found a little frustrating is that there’s a presumption that the stakes have to be ultra mega high. It’s like, it’s not planetary science fiction unless planets are cracking in half. It makes the world feel tissue-paper thin and kind of unrealistic. If the characters are unable to greatly affect the world they’re in, then the characters feel more realistic to me. So I like lower stakes. If there’s a cops and robbers story that takes place in New York City, the safety of the entirety of New York City is not at stake. At the end of Artemis, there is some city-wide danger and that was because my editor really really wanted there to be major stakes, so I put that in. But kind of reluctantly. I really feel like I would rather Artemis just be a setting, not something that needs to be saved.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

You chose a young, Saudi female protagonist. How did you create her?

Originally my story idea was completely different, and Jazz was a tertiary character. I needed a likable smuggler type and so I created her. I thought, what country haven’t I used yet, oh Saudi Arabia. Let’s make it a woman as well. She was just going to be in a few scenes. But that story, for reasons unrelated to her, was just not very good. So I came up with a completely different story and Jazz was more prominent but still not the main character. That story also didn’t work out. Then I said, well Jazz is interesting, I like her, let me see what I can come up with for a story that revolves around her. By the time I was writing Artemis, she was indelibly marked in my brain as being a woman from Saudi Arabia with her backstory and her troubles with her dad and stuff like that. My imagination would have rebelled if I tried to turn her into something I’m more familiar with like male or Christian or anything else.

How has your life changed since The Martian?

I quit my day job and now I’m a full-time writer. I live in a bigger house, I have a bunch of money. It’s all really cool, I highly recommend it. But the main thing for me is now I work alone all day. And I’m a pretty social guy so that’s actually kind of difficult. I miss the office environment that I used to work in. I was a software engineer, and I was going into work and saying “hey how you doing? Oh your dog was sick, how’s he feeling now?” You know, just being a team. I am still part of a team, with me my editor, my agent, my copy editor, my publicist, and all that, but it’s a different feel than when we’re all in a room next to each other working on some software and trying to get it to do what we want.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

What’s next for you?

I think I’m just going to stay on the moon for a while. I really like the setting of Artemis, and I would love to write a bunch of books that take place there. Not necessarily with the same characters, or even the same period in Artemis’ history, but I love the setting and I would like to write more. But that’s up to the readers. Basically it depends on how well Artemis does. If it does great, then I’ll write more that took place there. If people don’t like it then it’s on to other projects.

All the amenities: A NASA rendering of an inflatable spherical moon habitat housing six to 12, complete with a slanted top-floor running deck.NASA

Below is an excerpt from Andy Weir’s new book, Artemis.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

I live in Artemis, the first (and so far, only) city on the moon. It’s made of five huge spheres called “bubbles.” They’re half underground, so Artemis looks exactly like old sci-fi books said a moon city should look: a bunch of domes. You just can’t see the parts that are below ground.

Armstrong Bubble sits in the middle, surrounded by Aldrin, Conrad, Bean, and Shepard. The bubbles each connect to their neighbors via tunnels. I remember making a model of Artemis as an assignment in elementary school. Pretty simple: just some balls and sticks. It took 10 minutes.

It’s pricey to get here and expensive as hell to live here. But a city can’t just be rich tourists and eccentric billionaires. It needs working-class people too. You don’t expect J. Worthalot Richbastard III to clean his own toilet, do you?

I’m one of the little people.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

I live in Conrad Down 15, a grungy area 15 floors underground in Conrad Bubble. If my neighborhood were wine, connoisseurs would describe it as “shitty, with overtones of failure and poor life decisions.”

I walked down the row of closely spaced square doors until I got to my own. Mine was a “lower” bunk, at least. Easier to get into and out of. I waved my Gizmo across the lock and the door clicked open. I crawled in and closed it behind me.

I lay in the bunk and stared at the ceiling—which was less than a meter from my face.

Technically, it’s a “capsule domicile” but everyone calls them coffins. It’s just an enclosed bunk with a door I can lock. There’s only one use for a coffin: sleep. Well, okay, there’s another use (which also involves being horizontal), but you get my point.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

I checked my Gizmo for the time. “Craaaap.”

No time to brood. The KSC freighter was landing that afternoon and I’d have work to do.

We don’t have streets in Artemis. We have hallways. It costs a lot of money to make real estate on the moon and they sure as hell aren’t going to waste it on roads. You can have an electric cart or scooter if you want, but the hallways are designed for foot traffic. It’s only one-sixth Earth’s gravity. Walking doesn’t take much energy.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

The shittier the neighborhood, the narrower the halls. Conrad Down’s halls are positively claustrophobic. They’re just wide enough for two people to pass each other by turning sideways.

I wound through the corridors toward the center of Down 15. None of the elevators were nearby, so I bounded up the stairs three at a time. Stairwells in the core are just like stairwells on Earth—short little 21-centimeter-high steps. It makes the tourists more comfortable. In areas that don’t get tourists, stairs are each a half meter high. That’s lunar gravity for you.

Ground level is where all the tunnels connecting to other bubbles come in. Naturally, all the shops, boutiques, and other tourist traps want to be there to take advantage of the foot traffic. In Conrad, that mostly meant restaurants selling Gunk to tourists who can’t afford real food.

A small crowd funneled into the Aldrin Connector. It’s the only way to get from Conrad to Aldrin (other than going the long way around through Armstrong), so it’s a major thoroughfare. I passed by the huge circular plug door on my way in. If the tunnel breached, the escaping air from Conrad would force that door closed. Everyone in Conrad would be saved. If you were in the tunnel at the time … well, it sucks to be you.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

Aldrin is the opposite of Conrad in every respect. Conrad’s full of plumbers, glassblowers, metalworkers, welding shops, repair shops … the list goes on. But Aldrin is truly a resort. It has hotels, casinos, whorehouses, theaters, and even an honest-to-God park with real grass. Wealthy tourists from all over Earth come for two-week stays.

New York has Fifth Avenue, London has Bond Street, and Artemis has the Arcade. The stores don’t bother to list prices. If you have to ask, you can’t afford it. The Ritz-Carlton Artemis occupies an entire block and extends five floors up and another five down.

There was nothing in the shopping district I could afford. But someday, I’d have enough to belong there. That was my plan, anyway. I took one more long look, then turned away and headed to the Port of Entry.

Nautilus Members enjoy an ad-free experience. Log in or Join now .

Excerpted from Artemis by Andy Weir. Published with the permission of Penguin Random House. Copyright © 2017 by Andy Weir. 

Lead Photocollage Credits: Teri Rich / Shutterstock; NASA

close-icon Enjoy unlimited Nautilus articles, ad-free, for less than $5/month. Join now

! There is not an active subscription associated with that email address.

Join to continue reading.

You’ve read your 2 free articles this month. Access unlimited ad-free stories, including this one, by becoming a Nautilus member.

! There is not an active subscription associated with that email address.

This is your last free article.

Don’t limit your curiosity. Access unlimited ad-free stories like this one, and support independent journalism, by becoming a Nautilus member.