Centauri Dreams

Science fiction has always had its share of Earthside dystopias, but starflight’s allure has persisted, despite the dark scrutiny of space travel in the works of writers like J. G. Ballard. But what happens if we develop the technologies to go to the stars and find the journey isn’t worth it? Gregory Benford recently reviewed a novel that asks these questions and more, Kim Stanley Robinson’s Aurora (Orbit Books, 2015). A society that reaches the Moon and then turns away from it may well prompt questions on how it would react to the first interstellar expedition. Benford, an award-winning novelist, has explored star travel in works like the six novels of the Galactic Center Saga and, most recently, in the tightly connected Bowl of Heaven and Shipstar. His review is a revised and greatly expanded version of an essay that first ran in Nature.

by Gregory Benford

Human starflight yawns as a vast prospect, one many think impossible. To arrive in a single lifetime demands high speeds approaching lightspeed, especially for target stars such as Tau Ceti, about twelve light years away.

Generation ships form the only technically plausible alternative method, implying large biospheres stable over centuries. Or else a species with lifetimes of centuries, which for fundamental biological reasons seems doubtful. (Antagonistic plieotropy occurs in evolution, ie, gene selection resulting in competing effects, some beneficial in the short run for reproduction, but others detrimental in the long.) So for at least for a century or two ahead of us, generation ships (“space arks”) may be essential.

Aurora depicts a starship on a long voyage to Tau Ceti four centuries from now. It is shaped like a car axle, with two large wheels turning for centrifugal gravity. The biomes along their rims support many Earthly lifezones which need constant tending to be stable. They’re voyaging to Tau Ceti, so the ship’s name is a reference to Isaac Asimov’s The Robots of Dawn, which takes place on a world orbiting Tau Ceti named Aurora. Arrival at the Earthlike moon of a super-Earth primary brings celebration, exploration, and we see just how complex an interstellar expedition four centuries from now can be, in both technology and society.

In 2012, Robinson declared in a Scientific American interview that “It’s a joke and a waste of time to think about starships or inhabiting the galaxy. It’s a systemic lie that science fiction tells the world that the galaxy is within our reach.” Aurora spells this out through unlikely plot devices. Robinson loads the dice quite obviously against interstellar exploration. A brooding pessimism dominates the novel.

There are scientific issues that look quite unlikely, but not central to the novel’s theme. A “magnetic scissors” method of launching a starship seems plagued with problems, for example. But the intent is clear through its staging and plot.

I’ll discuss the quality of the argument Aurora attempts, with spoilers.

Plot Fixes

The earlier nonfiction misgivings of physicist Paul Davies (in Starship Century) and biologist E.O. Wilson (in The Meaning of Human Existence) about living on exoplanets echo profoundly here. As a narrator remarks, “Suspended in their voyage as they had been, there had never been anything to choose, except methods of homeostasis.” Though the voyagers in Aurora include sophisticated biologists, adjusting Earth life to even apparently simple worlds proves hard, maybe impossible.

The moon Aurora is seemingly lifeless. Yet it has Earth-levels of atmospheric oxygen, which somehow the advanced science of four centuries hence thinks could have survived from its birth, a very unlikely idea (no rust?—this is, after all, what happened to Mars). Plot fix #1.

This elementary error, made by Earthside biologists, brings about the demise of their colony plans, in a gripping plot turn that leads to gathering desperation.

The lovingly described moon holds some nanometers-sized mystery organism that is “Maybe some interim step toward life, with some of the functions of life, but not all…in a good matrix they appear to reproduce. Which I guess means they’re a life-form. And we appear to be a good matrix.” So a pathogen evolved on a world without biology? Plot fix #2.

Plans go awry. Backup plans do, too. “Vector, disease, pathogen, invasive species, bug; these were all Earthly terms…various kinds of category error.”

What to do? Factions form amid the formerly placid starship community of about 2000. Until then, the crew had felt themselves to be the managers of biomes, farming and fixing their ship, with a bit of assistance from a web of AIs, humming in the background.

Robinson has always favored collective governance, no markets, not even currencies, none of that ugly capitalism—yet somehow resources get distributed, conflicts get worked out. No more. Not here, under pressure. The storyline primarily shows why ships have captains: stress eventually proves highly lethal. Over half the crew gets murdered by one faction or another. There is no discipline and no authority to stop this.

Most of the novel skimps on characters to focus on illuminating and agonizing detail of ecosphere breakdown, and the human struggle against the iron laws of island biogeography. “The bacteria are evolving faster than the big animals and plants, and it’s making the whole ship sick!” These apply to humans, too. “Shorter lifetimes, smaller bodies, longer disease durations. Even lower IQs, for God’s sake!”

Robinson has always confronted the nasty habit of factions among varying somewhat-utopian societies. His Mars trilogy dealt with an expansive colony, while cramped Aurora slides toward tragedy: “Existential nausea comes from feeling trapped… that the future has only bad options.”

Mob Rules

Should the ship return to Earth?

Many riots and murders finally settle on a bargain: some stay to terraform another, Marslike world, the rest set sail for Earth. The ship has no commander or functional officers, so this bloody result seems inevitable in the collective. Thucydides saw this outcome over 2000 years ago. He warned of the wild and often dangerous swings in public opinion innate to democratic culture. The historian described in detail explosions of Athenian popular passions. The Athenian democracy that gave us Sophocles and Pericles also, in a fit of unhinged outrage, executed Socrates by a majority vote of one of its popular courts. (Lest we think ourselves better, American democracy has become increasingly Athenian, as it periodically whips itself up into outbursts of frantic indignation.)

When discord goes deadly in Aurora, the AIs running the biospheres have had enough. At a crisis, a new character announces itself: “We are the ship’s artificial intelligences, bundled now into a sort of pseudo-consciousness, or something resembling a decision-making function.” This forced evolution of the ship’s computers leads in turn to odd insights into its passengers: “The animal mind never forgets a hurt; and humans were animals.” Plot Fix #3: sudden evolution of high AI function that understands humans and acts like a wise Moses.

This echoes the turn to a Napoleonic figure that chaos often brings. As in Iain Banks’ vague economics of a future Culture, mere humans are incapable of running their economy and then, inevitably, their lives. The narrative line then turns to the ship AI, seeing humans somewhat comically, “…they hugged, at least to the extent this is possible in their spacesuits. It looked as if two gingerbread cookies were trying to merge.”

Governance of future societies is a continuing anxiety in science fiction, especially if demand has to be regulated without markets, as a starship must. (Indeed, as sustainable, static economies must.) As far back as in Asimov’s Foundation, Psychohistory guides, because this theory of future society is superior to mere present human will. (I dealt with this, refining the theory, in Foundation’s Fear. Asimov’s Psychohistory resembled the perfect gas law, which makes no sense, since it’s based on dynamics with no memory; I simply updated it to a modern theory of information.) The fantasy writer China Mieville has similar problems, with his distrust of mere people governing themselves, and their appetites, through markets; he seems to favor some form of Politburo. (So did Lenin, famously saying “A clerk can run the State.”)

Aurora begins with a society without class divisions and exploitation in the Marxist sense, and though some people seem destined to be respected and followed, nothing works well in a crisis but the AIs—i.e., Napoleon. The irony of this doesn’t seem apparent to the author. Similar paths in Asimov, Banks and Mieville make one wonder if similar anxieties lurk. Indeed, Marxism and collectivist ideas resemble the similar mechanistic theory of Freudian psychology (both invented by 19th C. Germans steeped in the Hegelian tradition)—insightful definitions, but no mechanisms that actually work. Hence the angst when things go wrong with a supposedly fundamental theory.

The AIs, as revealed through an evolving and even amusing narrative voice, follow human society with gimlet eyes and melancholy insights. The plot armature turns on a slow revelation of devolution in the ship biosphere, counterpointed with the AI’s upward evolution—ironic rise and fall. “It was an interrelated process of disaggregation…named codevolution.” The AIs get more human, the humans more sick.

Even coming home to an Earth still devastated by climate change inflicts “earthshock” and agoraphobia. Robinson’s steady fiction-as-footnote thoroughness brings us to an ending that questions generational, interstellar human exploration, on biological and humanitarian grounds. “Their kids didn’t volunteer!” Of course, immigrants to far lands seldom solicit the views of their descendants. Should interstellar colonies be different?

Do descendants as yet unborn have rights? Ben Finney made this point long ago in Interstellar Migration, without reaching a clear conclusion. Throughout human history we’ve made choices that commit our unborn children to fates unknown. Many European expeditions set sail for lands unseen, unknown, and quite hostile. Many colonies failed. Interstellar travel seems no different in principle. Indeed, Robinson makes life on the starship seem quite agreeable, though maybe tedious, until their colony goal fails.

The unremitting hardship of the aborted colony and a long voyage home give the novel a dark, grinding tone. We suffer along with the passengers, who manage to survive only because Earthside then develops a cryopreservation method midway through the return voyage. So the deck is stacked against them—a bad colony target, accidents, accelerating gear failures, dismay… until the cryopreservation that would lessen the burden arrives, very late, so our point of view characters do get back to Earth and the novel retains some narrative coherence, with character continuity. Plot Fix #4.

This turn is an authorial choice, not an inevitability. Earthsiders welcome the new cryopreservation technologies as the open door to the stars; expeditions launch as objections to generation ships go away. But the returning crew opposes Earth’s fast-growing expeditions to the stars, because they are just too hard on the generations condemned to live in tight environments—though the biospheres of the Aurora spacecraft seem idyllic, in Robinson’s lengthy descriptions. Plainly, in an idyllic day at the beach, Robinson sides with staying on Earth, despite the freshly opened prospects of humanity.

So in the end, we learn little about how our interstellar future will play out.

The entire drift of the story rejects Konstantin Tsiolkovsky’s “The Earth is the cradle of mankind, but humanity cannot live in the cradle forever.” – though we do have an interplanetary civilization. It implicitly undermines the “don’t-put-all-your-eggs-in-one-basket” philosophy for spreading humanity beyond our solar system. Robinson says in interviews this idea leads belief that if we destroy Earth’s environment, we can just move. (I don’t know anyone who believes this, much less those interested in interstellar exploration.) I think both ideas are too narrow; expansion into new realms is built into our evolution. We’re the apes who left Africa.

Robinson takes on the detail and science of long-lived, closed habitats as the principal concern of the novel. Many starship novels dealt with propulsion; Robinson’s methods—a “magnetic scissors” launch and a mistaken Oberth method of deceleration—are technically wrong, but beside the point. His agenda is biological and social, so his target moon is conveniently hostile. Then the poor crew must decide whether to seek another world nearby (as some do) or undertake the nearly impossible feat of returning to Earth. This deliberately overstresses the ship and people. Such decisions give the novel the feel of a fixed game. Having survived all this torment, the returning crew can’t escape the bias of their agonized experience.

Paul Davies pointed out in Starship Century that integrating humans into an existing alien biosphere (not a semi-magical disaster like his desolate moon with convenient oxygen) is a very hard task indeed, because of the probable many incompatibilities. That’s a good subject for another novel, one I think no one in science fiction has taken up. This novel avoids that challenge with implausible Plot fix #2.

Realistically considered, the huge problems of extending a species to other worlds can teach us about aliens. If interstellar expansion is just too hard biologically (as Paul Davies describes) then the Fermi paradox vanishes (except for von Neumann machines, as Frank Tipler saw in the 1970s). If aliens like us can’t travel, maybe they will expend more in SETI signaling? Or prefer to send machines alone? An even-handed treatment of human interstellar travel could shore up such ideas.

Still, a compelling subject, well done in Robinson’s deft style. My unease with the novel comes from the stacked deck its author deals.