Post-Colonial Science Fiction 1: Space Opera

Are humans the zebra mussels of the galaxy?

Glasgow 2024, the 82nd World Science Fiction Convention starts today. Sadly I’m not there, but to make up for my absence at least somewhat I am on writing retreat among the lakes of Northern Ontario. I’ve had a productive time in between kayaking and time with the friends around the fire; and, in the spirit of celebrating science fiction, I’ve written this piece honoring our past and looking to future possibilities. I hope you like it.

—K

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One of my goals with Unapocalyptic is to sketch the outline of 21st-century science fiction. I started this newsletter by writing about space settlement, but subsequently, I’ve mostly talked about more contemporary, Earthly issues. Taking a breather from all that dark ecology, this week we’re going back to space again, exploring worldbuilding and futurism on the final frontier, from a perspective that recognizes that the very idea of frontiers is, nowadays, fraught.

In “The Single-Family Space Colony,” I interrogated the framing of space colonization as a large-scale, civilizational effort. This time I want to talk about planets, and when it’s right, or prudent, to colonize one. We’ll come to a potentially depressing conclusion:

If there’s already life there, it’s a no-go for human settlement.

Now don’t get disappointed! This isn’t a bad position to take. It’s profoundly protective of our own biosphere and biology. And worlds with life on them—indeed, ‘habitable’ planets in general—may not be the best places to put a spacefaring technological civilization anyway.

Habitability vs. Colonizability

Habitability is the measure of highest value in planet-hunting. But should it be?

The Kepler space telescope found thousands of exoplanets, and the JWST is starting to fill in details about atmospheric composition, initially for big Jupiters but increasingly for Earth-sized planets too. We now know that most stars have planets and that a surprising percentage will have Earth-sized worlds in their habitable zone. Astronomers are fascinated by this region and what they can find there. Tantalizingly, within just a few years we may learn whether life exists outside our solar system. We will likely be able to calculate how common it is.

We generally assume that habitable planets are worlds we could move to and live on. If you start working through the details of settling other worlds, though, you’ll quickly realize that habitability and colonizability are not the same thing. Habitability refers to how likely it is that life could exist on a given world. Habitable worlds include planets that weigh eight times the Earth and have a surface gravity three times our own. Such a planet might be teeming with life, but humans could never live there.

This is also true for the fascinating, theoretical hycean planets. These are vast ocean worlds with hydrogen atmospheres and global, bottomless oceans. They could be hugely habitable because in addition to photosynthesis, they would have a highly efficient hydrogen/methane metabolism available to them. Their gravity would likely be higher than Earth’s, and the pure hydrogen atmosphere would usually be under high pressure. It’s unlikely you could ever open the faceplate of your suit and breathe in the salt air of such an alien sea—or even stand up without help.

I’ve been seeing disappointment amongst the astronomical community that Trappist-1c appears to have no atmosphere or barely one. It’s not in the habitable zone of its star anyway, so it’s been effectively struck off the list of attractive destinations. Yet this is ridiculous; with an equilibrium temperature of 60C, even a thin atmosphere will create a gradient across the terminator line of this tidally-locked world, guaranteeing that some locations are at room temperature. It is Earth-sized and has exactly the same gravity as Earth. It likely lacks water entirely but might have some glaciers at its night side anti-stellar pole. Thus, it could easily be settled with the usual dome-city approach beloved of classic SF stories. Orbital mirrors can light up zones in the night continents and vast regions could be given a 24-hour day/night cycle. On the day side—well, there’s this thing called air conditioning, and also blinds.

Despite not being habitable, c is eminently colonizable.

Hopping and Waving

For another example, take Mars and Venus.

I’d be the first to admit there’s a certain romance to Mars. It’s a planet superficially like Earth; our terrestrially-evolved simian brains can make sense of it. There are hills and gulleys there, craters, and towering volcanoes. You can walk on it. It’s at the outside edge of the Solar habitable zone. All this makes it seem reasonable to build a colony there.

Mars is easily visible in the night sky. It’s practically jumping up and down, waving us over.

In contrast Venus’s surface is an oven of toxic CO2 hot enough to melt lead and as highly pressurized as the bottom of the Pacific Ocean. It has a day longer than its year and is shrouded in a permanent haze of sulfuric acid.

Mars is obviously the better choice.

It’s all a big trick, though. Mars is fooling us. It’s luring us with a false promise of habitability while Venus hides a benign environment behind a Medusa’s mask of terrifying obstacles. In reality, while Mars may be more habitable, Venus is more colonizable. A single chart will show why.

Costing Your Ecosystem Services

I’ve created a simple economic scale to judge the colonizability of a planet. It has nothing to do with whether the world can sustain life; instead, it’s all about how many ecosystem services a colony gets for free. That is, how much of an ongoing maintenance cost is there to sustain a colony on that world? That cost sets nearly all the physical, social, and personal parameters for settling on a given planet. And when you do the costing, Mars does not fare well:

Cost of Ecosystem Services. Pale blue denotes resources that need a certain amount of industry and infrastructure, in an amount manageable for a small colony.

In this chart, Energy includes light for photosynthesis and electricity for industry. For plants, sunlight is free on Earth, but it’s attenuated at the asteroids, and weak and unreliable due to dust storms on Mars—therefore more costly at both. Sunlight is plentiful on Venus but not available on the 24-hour cycle that plants expect—and therefore despite its abundance, energy is likely to have a moderate cost there. On Trappist-1c, sunlight is abundant, but only on one side of the planet; and it’s weak in the frequencies that green plants like.

Industrial energy is cheap if it’s from solar panels on Earth, the moon, Venus and the day-side of Trappist-1c. It’s weak and unreliable on Mars, and very expensive by the time you get to the asteroids. If it’s nuclear power, it’s expensive and regulated everywhere. Wind power is possible but weak on Mars, abundant and powerful on Venus. So ultimately Venus’s power costs are closest to Earth’s, or even better.

Alien Biospheres

In his book Ecological Imperialism, Alfred W. Crosby shows how the first European colonies in the Americas failed because the colonists were only human. Later waves succeeded when the humans realized they needed to bring the species they depended on with them. It wasn’t European humans who conquered the New World; it was the European biosphere. Humans were, in a very real sense, just along for the ride.

The Great Lakes region where I live is currently threatened by zebra mussels. These are Crimean invaders who, unlike the Pilgrims, adapted immediately to the North American environment. They’re taking over—clogging drains and water pipes and pushing out native species. After 500 years, North America is crawling with invaders and humans are the least of the place's worries. As part of the ‘Columbian Exchange,’ all sorts of beasties crossed the pond in the other direction—syphilis, for example. It seems that Europe was already a crossroads ecosystem, however, and the impact on the Americas, isolated as they were since the ice ages, has been much worse.

Back in the early 1900s, when the classic space opera that Star Wars pays homage to was conceived, colonialism was still cool (for the colonizers) and ecology was not yet a science. Famously, Dune is the first major novel to talk about it. Back then, it was conceivable that humans could find planets with life on them and settle on them. In reality, any world with its own biosphere is going to either be so vastly different that our life forms are utterly incompatible—or one side of the exchange will have an advantage over the other. Remember the red weed that grows in sinister profusion across the land in H.G. Wells’s War of the Worlds? Some earthly microbe or plant could easily escape a human colony and ravage the colony world. Conversely, the native species might prove to be far better adapted to Earthly conditions than Earthly life. Riding in the nooks and crannies of returning starships, just as zebra mussels did in the holds of trans-Atlantic ships, alien interlopers could overwhelm our entire 3.5 billion-year heritage with just a few doublings of population.

Forget the aliens with the ray-guns; it’s the mold spores in their pockets we should be worried about.

Wells knew this, which is one of the reasons he’s still cool.

The amount of effort that would be involved in quarantining the colony from the native species is mind-boggling. The average human has a teacup’s-worth of bacteria living on us and in us (more actual cells than we have), and these are mostly commensal—we need them to survive. We also evolved to be awash in air and water filled with other species and to be crawled on and bumped into by all manner of critters. There is no such thing as an isolated human organism; if you did manage to create one, it would probably promptly die.

When we think about space colonization, we should picture earthlings doing the colonizing—not human beings but bundles of life forms, entire ecosystems traveling and settling other places. If there is already life in those places, then either one side will wipe out the other, or there will be en exchange of invasive species, and humans will be an afterthought when the winners are tallied.

Life is by far the hardest systems problem for a colony to solve. For this reason, and to protect our homeworld, the most prudent and practical strategy is for us to avoid setting foot on any planet that has its own native ecosystem.

This might turn out to include Mars. But while there are hints that there is life on Venus, it’s highly unlikely that it could survive in our environment, or us in its. Venus is right at the limit of colonizability, if it does have life. As we’ve seen, if it doesn’t, it’s the most benign environment in the Solar System, after Earth.

Post-Colonial Space Opera

The unspoken assumption here is that environments that have no life are ripe for exploitation. I almost agree with this; but I am one of the signatories to the Declaration of the Rights of the Moon, and am willing to concede the possibility of nonliving ecosystems—geosystems or astrosystems that may not be life as we know it, but may nonetheless deserve to be left alone. Not everything should be food for industry.

A post-colonialist science fiction recognizes that, and posits a thriving interstellar community on friendly colonizable worlds (for example, 100% Earth-like planets where life just never actually got started), but none on already-inhabited planets nor worlds of such uniqueness and beauty that they are treasures worthy of preserving. In this SF, you can imagine settlers walking the shores of previously sterile oceans on a planet with a relic oxygen atmosphere, and watching imported dolphins cavort past the mangroves the terraformers have planted.

Okay, but what does such an SF look like compared with the standard fare (especially space opera, which is a thoroughly reified subgenre built on colonialist assumptions)? We can find out by putting the above ideas in motion—that is, by doing a piece of worldbuilding around a possible post-colonialist space opera story or series.

I’ll call this story-world the Moiety, and describe some stories we can set in it.