After a close brush with death before Amazon swooped in to save it, The Expanse is officially back for a fourth season in December. Which means that if you’re not already obsessed with the space opera that blends interplanetary politicking and battles with alien monsters, you’ve got a few months to catch up. But it’s not just science fiction fans who can find a lot to love in this show—so can anyone concerned with the habitability of humanity’s homeworld.
The Expanse is set several centuries from now in a future where humans have spread across the Solar System. It focuses on the crew of the Rocinante, a rag-tag group of former ice haulers who get swept up in the biggest scientific discovery of all time, one that threatens to shift the balance of power between Earth, Mars, and the “Belters” eking out a living on asteroids and the moons of the outer planets. There are cinematic space battles, political intrigues, and Alien-esque horror elements. But in a pop culture landscape seemingly obsessed with superpowered humans and dragon-fueled destruction, the thing that makes the The Expanse truly stand out is how often it gets the science right, including showing how ill-suited bipedal primates are to life in the vacuum of space. And by addressing that reality head on, the show—whether intentionally or not—makes a powerful case for protecting the Earth.
To be sure, there are signs we’ve already screwed Earth up pretty badly. While we don’t get a ton of backstory on how the geopolitical landscape of The Expanse came to be, from the books (co-written by Ty Franck and Daniel Abraham under the pseudonym James S.A. Corey) we know Earth’s 30 billion inhabitants are governed by a muscled-up version of the United Nations which appears to have consolidated power in the wake of some major environmental disasters in the 21st century.
In a poignant shot from the show’s intro, we see that New York City—the seat of this supranational government—is surrounded by a giant seawall, suggesting that catastrophic climate change was one of the history-altering events. And while it’s possible the UN government has the climate situation under control by the events of the show, the planet is still buckling under the burden of its outsized population. Chronic resource scarcity manifests itself both in Earth’s economic structure (a huge percentage of people are jobless, living in overcrowded housing on Basic Assistance from the government) and in the fact that Earthers are deeply reliant on resources extracted from the Belt, fueling a colonialist power dynamic that undergirds much of the show’s drama.
No doubt environmental woes and overcrowding on Earth are one reason people began colonizing space in the first place. And yet, while the culture of the Belt is steeped in ideals of personal liberty and opportunity, these swashbuckling space pioneers face a host of survival challenges of their own that stem from a different environmental issue: Simply put, there is none.
Instead of a planetary environment, Belters have cramped, uncomfortable living spaces inside cargo ships and asteroids. They breathe recycled air, shower in recycled water, and eat endless meals of textured fungal protein. Things that we take for granted on Earth, like fresh produce and abundant oxygen, Belters value more than gold, and they’re often on the verge of running out.
And bare necessities aside, there are the more insidious challenges of spending a lifetime outside of Earth’s gravity well. Belter bodies are stretched and weakened to the point that mere moments on a planet’s surface can be torture, something that U.N. Deputy Undersecretary Chrisjen Avasarala exploits in a memorable scene from the show’s first episode. They’re prone to strange diseases, like the immunodeficiency afflicting some children who’ve grown up on Jupiter’s moon Ganymede. While the disease is an invention of the show, the possibility that a lifetime in space will cause our immune systems to go haywire is very real. So is the fact that we’d have to live deep inside rocks like moles to avoid becoming riddled with cancers from all the radiation exposure—and contend with whatever psychological idiosyncrasies, like extreme agoraphobia, such a lifestyle could cause.
By thoughtfully exploring the harsh realities of life in space, The Expanse reminds us that no matter where we go, we remain creatures of the Earth, dependent on a very narrow set of environmental conditions in order to survive. As the series’ multi-generational terraforming project on Mars reveals, those conditions are going to be incredibly hard to replicate. And even future humans’ best attempts to do so, like the farms on Ganymede station, are far more precarious and vulnerable than their Earthly counterparts. That’s not to say Earth’s environment isn’t vulnerable—the very premise of The Expanse tells us that it is, and if you read further along in the books, you’ll see just how much worse we humans can screw it up. But it’s telling that even after several centuries of life in space, Earth is still the only place that truly supports our existence. I suspect that whatever the crew of the Rocinante face in season four when they step foot onto a new alien world will only serve to reinforce that point.
Saturn’s rings and Jupiter’s moons have an alluring beauty in the show. But for soil and seeds, for a protective atmosphere and a (relatively) stable climate, Earth is still home. And since that’s liable to be the case for as long as we’re eating carbon and breathing oxygen, what The Expanse tells me is that we better damn well protect it.
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