As a child, Andy Weir loved space, but did not dream of being an astronaut. He wanted instead to be a flight controller: the person on earth telling folks up in the cosmos what to do.
The American author's debut novel The Martian (2011), about an astronaut stranded on Mars after being presumed dead by his crew, became a sleeper self-publishing phenomenon and was in 2015 made into a Ridley Scott film starring Matt Damon.
Weir, 45, is now shooting for the moon with Artemis, a heist caper set on a lunar city, borne out of his desire to write a novel about humanity's first city not on earth.
"The moon turns out to be this incredibly convenient place to colonise," he says over the telephone from London, where he is on a book tour.
He goes on to explain that one of the most common minerals on the moon, anorthite, can be smelted to produce aluminium and oxygen - aluminium to build a city, oxygen to sustain its inhabitants. "I just thought that was incredibly elegant - that the moon is made of, essentially, moon bases."
The Martian was anchored by resourceful astronaut Mark Watney, who survives on Mars by growing potatoes using human waste as fertiliser and producing water from rocket fuel.
Artemis' heroine, young smuggler Jasmine "Jazz" Bashara, shares Mark's drive to survive, but is otherwise poles apart. A wisecracking welder's daughter who was born in Saudi Arabia and scrapes by as a lowly porter in the moon's tourist economy, she hustles every chance she can get.
When she gets an offer to make a quick buck through some industrial sabotage, she jumps at the chance - but soon finds herself caught up in a city-wide conspiracy with a murderer on her trail.
Jazz was initially created as a minor character, says Weir, but proved such a lovable rogue that she swiftly took over subsequent drafts. There is no particular reason why he chose to make her of Arab ethnicity. "Artemis is a very international city and it made sense that the characters would be from all over the world. I thought, what's a country I haven't used yet? Saudi Arabia? And then, boop, there she was."
Artemis is likely to draw comparisons to Robert Heinlein's classic 1966 novel The Moon Is A Harsh Mistress, also about a lunar colony, although Weir says he was in fact more inspired by the neo-noir movie Chinatown (1974), a murder mystery involving water rights disputes in southern California. In Artemis, the resource that people fight over is oxygen.
He adds that while Heinlein is among his "holy trinity of science fiction" - the others being Isaac Asimov and Arthur C. Clarke - their books are very different. Heinlein's is a political treatise on libertarianism, while his is a light-hearted caper.
"I write to be predictive, not to preach," he says. "Other authors can do what they want - I don't feel any responsibility to try to project a social message or effect change. I just want to entertain."
Movie rights for Artemis were picked up by Fox even before the book was published. Phil Lord and Christopher Miller, the duo behind The Lego Movie (2014), have signed on to direct.
Should an Arab actress be cast in the lead role of a Hollywood science-fiction blockbuster like Artemis, it would break new ground in an industry notorious for whitewashing. The 2019 Disney live-action remake of Aladdin came under fire earlier this month for darkening white actors with make-up to make them look Middle Eastern.
While Weir will be no more than an "excited bystander" for the film adaptation, he says his one request is that Jazz be played by a woman who can pass as Arab. "Her skin colour should be that shade."
Almost all the scientific innovation in the book, he insists, exists today. "I would say it is even more scientifically accurate than The Martian."
Weir's father was a particle physicist and his mother an engineer. He grew up in a household saturated in science and went on to become a software engineer. "I wanted to be a writer, but I like regular meals."
His attempts to write on the side produced at first the "standard tale of woe" - a slew of rejections from publishers. Having given up on the traditional route, he began publishing The Martian a chapter at a time on his website, whereupon it unexpectedly exploded in popularity and was picked up by Crown Publishing.
"This is the best time in history to self-publish," says Weir, who is single. "There is no longer an old boys' network between you and the reader. You can sell directly to the reader for no risk on your part whatsoever."
Among his chief tips for aspiring authors is not telling anyone what you are writing until you have written it. "If you tell your friends and family, that verbally satisfies your need and reduces your will to actually get it written. Make a rule for yourself that the only way anyone experiences your story is to read it."
He hopes to write another story set in the world of Artemis. "It seems to have been a hit. Even negative reviews said they liked the setting."
But should humanity ever move to the moon, he would not be on that spaceship.
"I have no frontier spirit," says Weir, who has a fear of flying and can manage his punishing book tour schedule only under a lot of medication. "I like knowing that if I hurt myself, an ambulance can get to me in 15 minutes. I like being able to order pizza. I like being on earth."