Science fiction often assumes particular bundles of technology, even when the components of that bundle are not causally linked and might not appear at the same time. For example, authors generally assume energy-generating technology will keep pace with propulsive technology. To put this less obscurely, they assume that by the time faster-than-light drives show up, so will cheap, affordable, reliable fusion power plants. No doubt this is only partly driven by narrative convenience. We’ve been told fusion is only thirty years away for sixty years now. One can forgive authors for believing what turned out to be hopelessly optimistic predictions…although I am not sure why said authors also seem to expect fusion plants to be conveniently low mass, extremely efficient, and aneutronic.
However, some authors eschew the dream of commercial fusion (at least, of the variety that can be crammed into a spaceship hull) without abandoning the dream of interstellar travel. Not many, admittedly, but enough that five examples can be found.
Fifth Planet by Fred Hoyle and Geoffrey Hoyle (1963)
Despite technological progress driven by a century of nuclear rivalry between the United States, the Soviet Union, and other great powers (among whose number, the text makes clear, isolationist Britain cannot be counted), rocket propulsion remains lamentably constrained by the authors’ knowledge of physics. The best option on offer is a gaseous-core nuclear thermal rocket, whose performance, while vastly superior to chemical rockets, is woefully inadequate for the demands of interstellar travel. At least, it is in most circumstances.
Conveniently for would-be starfarers, the stars or at least a star is on its way to us. As surprised astronomers discovered in the 1990s, nearby Helios follows a path through the Milky Way that will pass within 20 AUs of the Sun midway through the 21st century. 20 AU is just barely within the ability of 21st-century technology to deliver a crewed rocket to Helios’ Earth-like world. As one might expect from a civilization that has invested a century in Cold War paranoia, none of the designers behind the project wonder if visiting an alien world is prudent. Nevertheless, it is a question to which they get an answer.
Gate of Ivrel by C. J. Cherryh (1976)
Nhi Vanye I Chya (Vanye)’s culture considers the domesticated horse as the acme of high-speed travel. Equines are for the most part not up to challenge of directly crossing interstellar distances. Thanks to the qhal gates found on so many planets, however, it’s possible to simply walk from one world to another. In theory, Stone Age hunter-gatherers could spread across the galaxy using the gates, provided they knew how to activate them. It would be no problem for Vanye on his horse.
As the mysterious figure who emerges from a qhal gate in front of Vanye explains, there is a catch. Qhal gates span time as well as space. One can step a century into the future, as Morgaine has. Alternatively, one could step into the past, inadvertently alter history and break time, as the qhal did immediately before they went extinct. Since the qhal left their incredibly dangerous gates behind, it is up to Morgaine and her new sidekick to track down and disable each continuum-threating relic.
Jem by Frederik Pohl (1979)
The rockets used to access orbit in the early 21st century are depressingly familiar—behemoths like the venerable Saturn V that consume stupendous amounts of chemical fuel to deliver laughably tiny payloads to orbit. Once in orbit, however, tachyon conversion drives make it affordable to litter the galaxy with grapefruit-sized uncrewed space probes. As long as one is content to settle for robotic exploration, it is surprisingly affordable.
Jem, the newly discovered habitable planet orbiting N‑OA Bes-bes Jeminorum 8426 AKA Kung’s Semistellar Object is sufficiently potentially valuable for the great factions of this relentless extrapolation of what turned out to be short-lived Disco Era trends to pay the eye-watering funds needed to deliver small groups of astronauts to orbit. Once there, it’s a simple tachyonic hop to Jem. Landing humans on an exoplanet is a glorious milestone in human history. It’s just too bad for 21st century Earth that one of the Disco Era trends relentlessly extrapolated is nuclear proliferation. It would only take a small spark to ignite World War Three and alas, a meaningless slap-fight over an alien world light-years away is just such a spark.
Flight of the Dragonfly by Robert L. Forward (1984)
Even if Volvo-sized, clean, affordable and reliable controlled fusion reactors remain a pipedream, there are other ways to access fusion power. For example, there’s a fairly sizable fusion uncontrolled reactor located a mere 150,000,000 kilometres away. The Sun squanders a literally eye-watering amount of energy into space—energy which cunning little monkeys like the human race could somehow exploit.
The light-sail starship Prometheus requires 1,500 terawatts to produce a hundredth gee acceleration. Sustained, it is sufficient to deliver explorers across six light-years to the planets of the Barnard Star System in just 40 years. The Sun can provide the energy needed. All humans need to do is create is a Brobdingnagian thousand-laser system consuming civilizations-worth of power, and then maintain it for decades. Then, all one needs is a collection of researchers comfortable with the reality that while this vast apparatus can deliver them to Barnard’s Star, it cannot then retrieve them.
Far From the Light of Heaven by Tade Thompson (2021)
Einstein-Rosen bridges tackle the heavy lifting involved in traversing interstellar distances. Ragtime, the interstellar starship that will deliver Michelle “Shell” Campion and a thousand colonists to Earth-like Bloodroot, is powered by sophisticated examples of familiar technology: bioreactor, fuel cells, and solar panels. Ragtime’s highly advanced conventional power sources are sufficient to deal with the shorter distances involved in travelling to and from the bridges, while the ship’s sophisticated life-support systems keep the passengers alive but quiescent for the decade Ragtime takes to travel from bridge to bridge.
Decades of incremental technological progress have eliminated all possible bugs. Shell goes to sleep knowing Ragtime’s infallible systems will deliver her and her charges safely to Bloodroot. Regaining full consciousness to discover that Ragtime’s AI is quiescent, while the ship itself is littered with the dismembered body parts of murdered passengers is utterly unexpected. Most of the passengers are still alive, however, and if Shell can work out who the killer is and stop them, the remaining passengers might survive.
***
No doubt you all have your own favourite example whose absence above astounds you. Feel free to mention them in the comments.
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 the Aurora finalist Young People Read Old SFF (where he is assisted by editor Karen Lofstrom and web person Adrienne L. Travis). He is a four-time finalist for the Best Fan Writer Hugo Award and is surprisingly flammable.
Strictly speaking, that should be “interstellar flight…”
@1: Congratulations on posting the correction (as a comment) before the hordes of commenters like me swoop in to do it for you. Too bad 90% of those arriving after comment #10 won’t read comment #1. :(
Also, I do remember seeing somewhere how Forward published a revision of his lightsail scheme that would allow return to Earth. After arrival at the destination star and a period of exploration, the ship opens its sail again and immediately releases another ring. Much like the deceleration phase, this second released ring reflects laser light from Earth back onto the reverse side of the remaining sail attached to the ship, accelerating it back Earthwards.
The first thing that came to my mind was Pohl’s “The Gold at the Starbow’s End,” later expanded into Starburst. The ship in each case had some sort of interstellar drive to begin with but ended up being greatly accelerated by thinking real hard, IIRC.
The second thing was Alan Dean Foster’s “Thrust,” which also features a ship with an interstellar drive which gets accelerated, in this case by sex, somehow. He said in an introduction it was inspired by Poul Anderson’s story or novel about the beer-powered spaceship, neither of which I have read.
Huh. That’s a Foster new to me. I’d have thought Norman Spinrad’s The Void Captain’s Tale (1983) and Child of Fortune (1985) (in which starships are powered by orgasmic energy) a more likely source of inspiration than A Bicycle Built for Brew AKA The Makeshift Rocket…
James @1: Apologies! The URL/link will have to remain the same, but we’ve updated the headline…
The comment about the ship powered by passengers walking inside it somehow reminds me of Ada Palmer’s Terra Ignota series, which I’m currently re-reading to prepare for a read of the final volume. It features a society shaped by the existence of a vast network of super-fast flying cars. What fuel do 8*10^8 cars consume as they fly at speeds up to 1000 km/hr? We are not given the slightest clue — they just do.
@@.-@ No doubt they would have been, except that “Thrust” was published in 1979.
2: Given that I have had people pop in to suggest works that were literally the first work I mentioned…
I don’t know how I missed Thrust. 1979 is within my peak Foster reading years.
@2: I thought Forwards original work had the conversion of sail to mirror focused on smaller sail, but it didn’t allow return, it merely allowed enough deceleration to be able to actually stop at the target system instead of just surveying it as you shot past.
Re Terra Ignota — there’s lots of tech that isn’t explained in the book. Likely either the narrator doesn’t know, or doesn’t care. But, they are clearly illustrated as having a high-density power-source on board when they start to blow up occasionally.
A perhaps more interesting omission is how do they actually fly?
Can anyone point me to the unnamed book in footnote 1? I’m dying of curiosity and Google searches avail me not.
Here’s a hint!
@13 Thank you! I’d read some of that author, but not that particular one.
@13,
A lot of the science in those books leaves me, well, screaming in disbelief.
The microorganism in Hail Mary by Andy Weir is another intriguing plot device. Quite a few authors use other forms of handwavium, including zero-point energy.
Man, that cover on Gate of Ivrel. That’s very early Michael Whelan, quite clearly still under the strong influence of Frank Frazetta.
Doug M.
Speaking of screaming, @15, there’s Venus on the Half-Shell by Kilgore Trout (alias Philip José Farmer). Interstellar flight is powered by drawing on the energies of stars in an alternate dimension. This causes the living stars of that dimension to, literally, scream in pain as there energies are drawn away. Oh, it also results in the death of said stars. So there is an end to FTL in sight. Oh, and as an additional bonus all but one Earthling human is killed by a flood caused by cosmic bureaucrats.
Dune? Bending space by ingesting a drug seems like an interesting way to travel
Davids #6 and #11: The fourth book in the Ada Palmer’s Terra Ignota series does reveal, offhandedly, the source of energy powering the cars. The hard-SF-loving reader will not be entirely satisfied but (1) it is implausible without being completely impossible, which is good enough for fiction, (2) hey, you’ve come this far, go with it! and (3) the hard-SF-loving reader should have understood from unambiguous signaling in the first chapter of the first novel that this was not going to be a strictly hard science fiction story.
The powering the ship by walking in that particular VERY POPULAR series was a real jerk me out of the suspension of disbelief moment!
Footnote 4: So we’re not talking about The Shadow of the Ship here.
@10: You are correct. In both the Rocheworld novels, the laser tech stops with delivering the ship to the Barnard system. But in his paper Roundtrip Interstellar Travel Using Laser-Pushed Lightsails (1984) he describes the next step: detaching a second ring at the start of the return trip.
@jimjack: the next Dune novel will be called Dune: Drug Addicts in Space! It will somehow be both a prequel and a sequel at the same time.
@Sunspear: Perfect. I’m not fan of the ‘new’ Dune books but this one has potential.
@@@@@ 3 Dan Blum:
He said in an introduction it was inspired by Poul Anderson’s story or novel about the beer-powered spaceship, neither of which I have read.
Poul disliked the new title some magazine editor slapped on the story: A Bicycle Built for Brew. In all republications he had influence on, it was The Makeshift Rocket.
I prefer the first title, as better fitting that humorous farce.
Dune FTL travel is accomplished by the Holtzman drive, which allows travel through another dimension (folded space) en route to destination. What the spice does is give a limited form of prescience, allowing the navigator to avoid dangers in folded space. Without the spice, a fair number of ships were destroyed during travel.
There was also a pre-Guild form of FTL which didn’t involve folded space.
An interesting article, as always, and a good selection of books using different propulsion methods. And thanks for the mention of aneutronic fusion reactors. They are almost as nifty a concept for SF stories as “cold fusion,” which unfortunately proved to be a dead end.
In Poul Anderson’s The Avatar, entire spaceships were moved from star to star using a Tipler machine; a huge dense cylinder spinning at near light speed. No relativistic time distortion was involved.
@16, that Gate of Ivrel cover is not only influenced by Frank Frazetta, but is a direct parody of Frazetta’s usual style since the roles are gender swapped from similar art of that time. That didn’t actually occur to me till decades later, but I’m quite sure it was deliberate, both to reflect the plot of the book (I believe Whelan would actually read the books before painting the covers!), and of course to sell more books. He also did some interior art for those books, which I wish more books would have.
@ryozenzuzax: Excellent point. That is exactly how the Holtzman Drive works. I suppose it might not fit into the parameters of this article. I do love the concept of folded space and the Navigators. Like most of Dune, a brilliant creation.
The notion that Fred Hoyle suffered from a lack of knowledge of physics is risible.
https://en.m.wikipedia.org/wiki/Fred_Hoyle
His credentials, also, do nothing about his numbers not working. Still, better than his Into Deepest Space, in which Jupiter seems to be 7.5 million km from Earth, about one twentieth of the distance between the Earth and the Sun, the distance to Alpha Centauri is 3 light years and the distance to the center of the galaxy is 4000 light years, not to mention the interesting tidbit that speed and pressure can substitute for gravity.
Forward’s Flight of the Dragonfly also points out an important problem with leaving your engine at home while your laser sail starship undergoes a multi decade mission.
The astronauts are at the mercy of the people back home responsible for the running and maintenance of the laser array. In the novel, a corrupt politician in charge of the laser array congressional comittee steals money meant for a vital expansion of the laser lens. He is exposed, but too late to expand the lens in time. The astronauts and the mission is doomed.
Luckily scientist invent a laser frequency doubling material that removes the need for a larger lens
In Arthur C. Clarke’s Childhood’s End, the Overlord starships are STL but travel at near lightspeed. This requires absurd amounts of energy.
The good news is the ship engines can directly tap absurd amounts of energy from the Sun or other star.
The bad news is the tapping range is only a few AU. This means the starship has to accelerate from zero to near c in only a few AU. This would turn the starship into ionized plasma in a few nanoseconds, with a one ion thick layer of former ship’s crew plated over the anti thrustward bulkhead.
The good news is the Overlord’s engine is that technobabble kind whose thrust acts equally on all the molecules in the action radius, so the starship and crew are in free fall during acceleration.
The starship coasts at relativistic velocity, safe in the arms of St. Einstein.
The process is repeated at the destination star to decelerate.
Charles Martin @31
Hoyle was very good at, for instance, working out implications of nuclear fusion reactions. This does not guarantee he was very familiar with the implications of stellar motions in the galaxy, however.
We’ve been told fusion is only thirty years away for sixty years now.
Now, now, I remember when the perpetual delay time was “forty years away”, so there’s been progress! (Sort of.)
Probably the humans in Childhood’s End were too paralyzed with fear over the implications of being conquered by a technologically superior civilization to focus on the fact that NAFAL drive lends itself to bombarding planets with r-bombs.
James Blish: the “Spindizzy” drive (in the Cities in Flight books), which seems to spin molecules in a way that, uh — technobabble.
Peter Hamilton: in the “Commonwealth” series, people ride from planet to planet on choo-choo trains. No, really…
I wish I could remember where the idea of the “irrelevancy” drive comes from. Essentially, create a bubble of space around you which is so completely out of contact with the rest of the universe that time and distance become, well, irrelevant. I have this vague idea it’s from Heinlein, but I can’t recall where.
Nobody’s mentioned the Infinite Improbability Drive?
I’ve had two silly ideas of my own over the years, which have never made it into stories but worked well in TTRPGS:
1. Coordinate Protocol for Acceleration through Semantic Engineering (CPASE, or “twisted space”) — the idea being that a sufficiently powerful mentality could, by selective observation, redefine its own coordinates wrt spacetime.
2. It never had a name, but…taking the c-limit and choice of metrics very seriously and sort of ignoring a few other aspects of realtivistic physics … choose a spinning reference frame, but choose it as still, so the rest of Universe is circling around you. Say the reference frame has the Universe circling around at a rate of 60 RPM. Then the most distant object observable object, in the plane of rotation, is going around you at a rate of once per second. Its distance from you is a radius r, and the circumference of its orbit is equal to 2πr. Since it can’t be traveling faster than c relative to you, that circumference is, at most, 1 light second, so the maximum possible value for r = 1/2π light seconds. Spin faster and r decreases. At 6000 rpm, everything observable on the plane of rotation is within 1/200π light seconds, or less than 50,000 km (lt 30,000 miles). Now you need a set of thrusters mounted around you on the plane of rotation. Fire them in synchronized bursts, such that they fire only when they push you in the direction you want to go, and something like Alpha Centauri can be reached in reasonable time at 1G acceleration, and even the Andromeda nebula is not out of the question.
Yes, I know why it doesn’t work. Don’t care, it’s good enough for a TTRPG or a hard(ish) science fiction novel…
John W. Campbell used the fact that an object’s kinetic energy differs according to context (that is a baseball has one kinetic energy wrt Earth and a different one wrt Mars) to argue conservation of energy didn’t exist.
The superhumans in A Certain Scientific Railgun redefine physics in their immediate vicinity. I don’t see why this could not produce living FTL drives….
There is the bloater drive from Harry Harrison’s Bill the galactic hero.
It increases the distance between atoms causing the ship, and you to increase in size. Light years in size. Then the leading edge of the ship is put in focus, then the ship is shrunk, and presto you’re there.
Clarke’s Quantum Ramjet in “Songs of Distant Earth” is another example. Sadly his Asymptotic Drive in “Imperial Earth” is total baloney, as accreting micro-black holes put out, at most, 6.4 W per kg of their mass. And it wasn’t using Hawking radiation, since the main character spies on it in the engine chamber in one scene – no Hawking radiation to be seen.
But Sheffield’s Kernels were based on more up-to-date black hole physics, so the Assembly in his early McAndrews tales are propelled by extracting energy from rotating BH’s aka Kernels
Baxter’s similar handwavium in “Proxima” and “Ultima” are zero point energy sources that even the ancient Romans could figure out to build starships. Or the Aztecs. Curiously there might be a real energy source trapped in asteroids – quark nuggets. Marshall Eubanks has published multiple papers about finding them in fast rotating asteroids, while there’s other researchers who have documented possible falls of nuggets to the Earth’s surface. They can catalyze fusion or be used to make antimatter at super-high efficiency.
Mention of “irrelevance” – the phrase is Heinlein, Time For the Stars, but the sense is a bit different. They discover that relativity theory is flawed because there is in fact true simultaneity and infinite speed when telepathy is involved. The main part of the book is about the “twins paradox” with actual twins.
@0
And comfortable with the fact that during the trip they will be drugged such that their aging slows, but their mentalities will be reduced to the kindergarten level.
@31: Everyone makes math mistakes. Asimov once wrote a science article with an error of 23 orders of magnitude in one calculation (Linus Pauling wrote him a polite note about the error, without saying precisely where the error was).
@Dan’l: “Peter Hamilton: in the “Commonwealth” series, people ride from planet to planet on choo-choo trains. No, really…”
You’re being silly, but misleading. The choo-choos are irrelevant. People, small planes, other vehicles, could enter the event horizon of the stargates/farcasters/wormhole terminals (whatever you want to call them) and emerge at the destination end. They could step through while walking.
I don’t remember how the network was built exactly, but I think actual starships had to get there first to build the receiver gates. So basically the Earth side of it looks like a combination airport/train station with various glowing portals at track terminals.
E. E. Doc Smith had his “inertia-less drive” which allowed spaceships to zip around the galaxy. Totally implausible, but highly creative. It also made me ask my dad, “What’s inertia?”
Five-Twelfths of Heaven by Melissa Scott– somehow, alchemical symbols is used for ftl.
#40: I thought it was the space ship becoming very large and diffuse was from Christopher Anvil. In any case, I remember the stars as tiny and very bright inside the spaceship.
The problem of interstellar travel is one that I tackled in my own novel, “The Star Sailors” (hdbk St. Martin’s Press, 1980; ppbk Author’s Choice Press 2009) by bringing in both “metarelativity” and quantum theory. Years later, when I was at NASA, I cohosted a workshop on faster-than-light (FTL) travel at the Jet Propulsion Laboratory. One of the guest speakers was Dr. Robert L. Forward.
I know of no way to travel at FTL speeds but I am also aware that there was a time when people envisioned travel to the Moon by whirlwinds and geese. But we’d better find a way to travel to the stars because as James Strong wrote in his 1965 book “Flight to the Stars”, “the reward is survival”.
@45 Timothy Zahn’s Quadrail series of books does, in fact, have trains through interstellar space. Makes reasonalble sense in story and they’re a great set of mystery/investigator novels with an SF background. IMO of course.