When it comes to crossing the vast gulfs between the solar system and other stellar systems, SF writers turn to two main solutions: small and fast1 or big and slow. Perhaps the best known example of big and slow is the generation ship, large enough to qualify as a large town or even a small nation, slow enough that entire lives will be consumed getting to its destination.
Generation ships live in that delightful overlap between seemingly practical and nearly certain to inflict lives of deprivation and misery on their inhabitants. You might wonder what sort of person imagines the immiseration of many many others. SF authors do. Misery is drama. Generation ships offer so very much drama.
Two 20th century authors wrote stories sufficiently remarkable to imprint the essential details of their plot on many—most?—of the generation-ship stories that followed. The best known is Robert Heinlein’s Orphans of the Sky, a fix-up of the 1941 novellas Universe and Common Sense. A young man makes the (ahem) Astounding discovery that what he took for the whole world is instead a spacecraft lost in the vast depths of space. Mutiny and mass death have led to barbarism and communal amnesia about the ship’s origin, while radiation and blind prejudice have created a never-ending war between the mutants and their “normal” cousins. Given enough time, all of the life support systems on the ship will break down, so landing the ship while these systems still work would seem to be the obvious course of action. However, it’s hard for the masses to give up their superstitions long enough to organize escape.
Years before Orphans, however, there was Murray Leinster’s 1935 “Promixa Centauri.” The voyage in “Proxima” lasted only seven years, and the Adastra managed to arrive at the system for which they had originally aimed. That seven years was still long enough for the social order to break down, for the crew to divide itself into the command crew (still clinging to power) and the restless “Mut” majority2. Fortunately, the natives of the Proxima system don’t care about the entrenched divisions of human society; they are far more interested in the fact that both loyalists and Muts are made of meat. Tasty, tasty meat. Truly, there are no social problems that applied carnivory cannot resolve.
A surprising number of authors have written variations on Leinster and Heinlein’s plots, stories in which bold explorers head towards distant worlds, only to fall into barbarism, genetic degeneration, and doom along the way. Going by works like Mayflies, Captive Universe, End of Exile, The Starlost, and others, generation ships are one means to protracted abuse of one’s descendants. A choice which will doubtless ensure the undying hatred of the poor progeny.
Even when, as in the case of Stephen Baxter’s Mayflower II, some attempt is made to avoid degeneration and eventual extinction, that effort does not seem to help much. Lesson: do not put a do-nothing immortal idiot in charge of implementing the plan.
But not every generation ship ends up drifting lifeless and slowly cooling in the galactic abyss or careening directly into a star. A very lucky few are like The Dazzle of Day’s generation ship Dusty Miller, whose 175-year journey and eventual settlement on an alien world succeed because the passengers are Quakers, essentially decent people who wouldn’t think of eating each other. Still, the generation-ship success-rate is low enough that I recommend anyone who suspects they are in a generation ship novel master the lyrics to Gir’s Doom Song.
There may be a way to make the generation ship concept actually work. The essential issue is, as Natalie Zutter once explained, that even large spaceships are probably going to be small compared to the Earth; hence their resources, cultural and otherwise, will be insufficient for the challenge of interstellar travel. We know that the Earth very definitely can support entire civilizations for millennia. Why not simply use the Earth itself as our generation ship?
Novels like Sins of the Father and A World Out of Time aside, affixing rocket engines to planets is likely to prove impractical. The answer is to cultivate patience and spend the centuries and millennia on our comfortable human concerns while the stars come to us. The stars of the Milky Way are in constant motion, their distances always changing. At present the nearest star is an inconvenient 4.2 light years away, but as recently as 70,000 years ago Scholz’s star was a picayune 52,000 astronomical units away!
We missed our chance to visit Scholz’s Star, but Gliese 710 may present an even more promising opportunity. Whereas Schotz’s Star is just a run-of-the-mill red dwarf with a brown dwarf companion, Gliese 710 is a comparatively sun-like star. Even better, its closest approach may be even closer than Schotz’s Star, a mere 13,000 AU, perhaps less. Perhaps much, much less, although I suppose a pass through the inner system is too much to hope for.
Still, even 13,000 AU would be a challenge for present technology. It took New Horizons about a decade to cover the 40 AU to Pluto. 13,000 AU is much larger than 40 AU. Not to worry. We have time to work on our spacecraft. Gliese 710 is at present just under 20 parsecs away. At its current breakneck speed towards us, it should be here in just 1.3 million years.
1: Sometimes even faster than light. Although no credible evidence exists that the speed of light can be exceeded, writers are willing to embrace the possibility that light might be outpaced somehow. Never underestimate the persuasive power of somehow.
2: “Mut” stands not for mutant but mutineer.
In the words of Wikipedia editor TexasAndroid, prolific book reviewer and perennial Darwin Award nominee James Davis Nicoll is of “questionable notability.” His work has appeared in Publishers Weekly and Romantic Times as well as on his own websites, James Nicoll Reviews and Young People Read Old SFF (where he is assisted by editor Karen Lofstrom and web person Adrienne L. Travis). He is surprisingly flammable.