Everybody loves a huge space empire. A far-flung interplanetary civilization combines the romance of exploration with the pride and cool-factor of building something. But not every star-spanning regime is a viable proposition. Here are 10 star-empires from science fiction that make economic sense.

Top image: Leviathan Wakes, cover art by Daniel Dociu.

The main problem with an interstellar (or even interplanetary) empire is justifying the immense costs of traveling from one world to another — there have to be goods or services valuable enough to justify shuttling back and forth and maintaining control over multiple planets. This is especially the case if you rule out faster-than-light travel, but it's going to be an issue in either case.

(Because the economics of interstellar trade are actually quite challenging.)

So here are some space empires from science fiction that actually have an economic rationale:


Image: La Saga Vorkosigan, art by Jose Maria Beroy

1) The Vorkosigan Saga by Lois McMaster Bujold

In Bujold's universe, wormholes allow quick travel between star systems, and terraforming is relatively commonplace. And this relatively easy transit, combined with lots of commodities worth trading, make for a regime with a solid economic basis, the Barrayaran Empire. A lot of planets have unique goods to trade — one planet produces "butterbugs," which host a microbial suite that produces a non-perishable "perfect food."


2) The Foundation Series by Isaac Asimov

In the case of Trantor, the capital of Asimov's Galactic Empire, the main point of the economic arrangement seems to be obtaining food. Trantor grows to the point where the entire planet's surface is covered with city, with 40 billion people living there and administering the Empire. So food has to be imported from other planets, via one-person interstellar spaceships that run on atomic energy. This isn't exactly an efficient system — you'd imagine people on Trantor would get pretty tired of frozen peas, and Trantor's vulnerability to siege is a major factor in its inevitable doom — but at least you can see why it works. As long as transporting food is cheaper than telepresence technology that would allow some of those 40 billion people to live closer to farms, anyway.


3) Neptune's Brood by Charles Stross

Probably no book has spent as much time discussing the intricacies of interstellar trade and economics as this one. And the main invention that makes this whole system possible, in the absence of magical FTL travel, is "slow money" — as we put it in our review, this is "money whose very lack of liquidity makes it a stable investment tool for millennially long term projects." Which makes it a unique financial instrument... and uniquely vulnerable to a particular scam.


Image: Carel De Winter

4) Downbelow Station by C.J. Cherryh

The opening pages of this novel actually spend a lot of time discussing the economics of the Alliance-Union universe. The main scarce commodities are precious rare ores, which can only be mined outside the solar system, and "biostuffs," which can only be produced affordably on a few planets. At first, Earth is the source of all "biostuffs," giving the Earth Company absolute control over the miners on the outer worlds — until another planet that can produce "biostuffs," Pell, is discovered. And the existence of another world that can produce food for humans allows the outer stations to become independent and create their own quasi-empire. Soon, other words with food sources are discovered, including Cyteen, Fargone, Paradise and Wyatt's. The basic economic model, though, remains "food for ore." (A better trade, probably, than Asimov's "food for bureaucracy.")


5) Firefly

Yep, here's the only television show on this list — because Joss Whedon's Firefly devotes quite a bit of time to the economics of the huge star system where Mal Reynolds operates. The main device that makes the Alliance and the Outer Worlds economically plausible? Imperfect terraforming. We've terraformed a ton of planets, but haven't done all that great a job of it, meaning that there's a constant need for goods (foodstuffs and medicines) on those outer worlds, which are by no means self-sufficient. Plenty of work for a guy like Mal Reynolds, in other words.


6) The Night Dawn Trilogy by Peter F. Hamilton

In Hamilton's trilogy, humanity is ruled by the Confederation, but is divided into two major factions, the Adamists and the Edenists. The Edenists mostly control the economy, because they have a monopoly on harvesting helium 3 from gas giants — the fuel source which everybody uses to power their starships. The only other viable fuel source, antimatter, is illegal because it could be used as a weapon.


Image by LSGG

7) Dune by Frank Herbert

As with a lot of the examples on this list, the economics of Dune rely on scarcity — the planet Arrakis is the only source of the Spice, which you might have heard "must flow." Arrakis, meanwhile, is a desert hellhole where water is incredibly scarce. Spice is the magical item that makes interstellar travel possible, by facilitating the "navigation trance."


8) The Expanse by James S.A. Corey

This series is often compared to Firefly, in terms of its focus on people who are just getting by. We follow the crew of a cargo vessel hauling ice around the asteroid belt — the smaller ships haul ice and other commodities, while large corporations deal in more high-profit items. Later in the series, interstellar travel becomes possible, and a thousand worlds open up.


9) 2312 by Kim Stanley Robinson

Robinson's future solar system is actually a planned economy, which he's described as a "funhouse mirror" version of our system. The economic necessities are all controlled by the Mondragon, a civilization that provides for everyone's needs — but there remains a capitalist system that trades in luxuries, or "above and beyonds." A big part of the viability of this system rests on the use of asteroids, both for transport and as artificial biomes, or "terrariums."


10) The Space Merchants by Fredrik Pohl and C.M. Kornbluth

This is a largely corporate-controlled Earth, which is in the process of colonizing Venus and other planets — and the big widget that makes the economy viable is the fact that most products sold by the corporation have addictive substances in them, from candy to cigarettes. Also, food and fuel are very scarce, and scarcity always makes for good economics. This satirical dystopia, co-written by a former ad man, is one of the sharpest novels about economics you'll ever read.


Sources: Rocketpunk Manifesto, Project Rho, SF Signal. Additional reporting by Abhimanyu Das. Thanks to Annalee and Danny for the input!

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