“Will, if we’re not on Mars, you tell us where we are?” “I’m not sure yet, we might even be on Cerberus.” Cerberus? So asked Penny Robinson to her older and brainier brother Will Robinson in “Lost in Space”. For a long time I wondered what they might be talking about…until I realized, when worldbuilding for my own science-fiction universe, that this “Cerberus” might have some connection to the star Sirius.
Specifically it might be a planet or some such in orbit. Cerberus was the three-headed dog of Greek mythology, the guardian of the underworld, and a canine association (Sirius is the “dog star” and the leading light of the constellation Canis Major, i.e. the Big Dog) only makes sense for nomenclature.
True, one might object that the writers of “Lost in Space” didn’t think it through this much, but Irwin Allen’s science fiction shows were surprisingly hard sci-fi in some respects, and since the premise of the show was that they were originally headed to Alpha Centauri but got off-course, a planet orbiting Sirius (called Cerberus) would be an obvious alternate possibility for where they ended up (Sirius is 8.6 light-years away from Earth, only about twice as far as Alpha Centauri’s 4.3 light-years).
A Cerberus might also be a fine alternate possibility for an interstellar expedition: oh, Alpha Centauri is the obvious candidate, by far, but the twin suns of Alpha Centauri are the only sun-like stars until you reach Sirius; every other star between Alpha Centauri and Sirius’s distance is a red dwarf. Whereas Sirius consists of a blue giant star and a white dwarf, a more exotic sort of sun than your average every day red dwarf: indeed, Sirius is the closest star that’s significantly more massive (or bluer) than our own sun.
So as someone who has already written up the story of mankind’s first interstellar leap in my universe, “Letters from the Airy Deep”, an expedition to Sirius would be the obvious follow-up, the next giant stride in humanity’s grand adventure. What might that look like in my world?
Well, in as much as Proxima Centauri in my universe hosts a water world, Thalassa, I’d want a contrast…and my “ultimate desert coast” worldbuilding project just might provide it. You can read the whole post, but in short, it’s a world that, like Thalassa, has an almost pure oxygen atmosphere, but one that instead of being very thick is very thin. At sea level, it’s only a tenth as thick as Earth’s, the partial pressure of oxygen being near the lower limit of human survivability even with high-altitude adaptation. Temperature ranges are wide: 60 degrees Fahrenheit by day and 0 by night, even on the coast where the weather is more moderate. And the climate is hyper-arid: no significant precipitation falls in this world. Water temperatures hover perhaps around 20 degrees Fahrenheit, but high salt content keeps it liquid down to temperatures much lower than that, and lends it an exotic quality (like in the Dead Sea, human swimmers might float very easily).
The latest twist in my story for this planet (let’s call it Cerberus if we’re placing it in Sirius) involves the concept of the continents being dominated by spires similar to Devils Tower in Wyoming: ancient volcanic plugs that have eroded away, leaving a landscape of sheer vertical cliffs with plateaus up top. The cores of the continents might be a contiguous plateau, but they break up as you move further out into ever-more tenuous archipelagos. I’m picturing the high plateaus of each continent as reaching roughly the same altitude, perhaps the result of some ancient tectonic upheaval (perhaps the way tectonics works on Cerberus). And this will be a high altitude indeed: given the great tectonic upheavals of this world, as well as the lower gravity (the thin atmosphere means the world is likely smaller than Earth), I could easily picture altitudes of 50,000 to 60,000 feet above sea level being reached…from near-vertical cliff faces that rise directly out of the ocean.
But this won’t be a mere copy of Devils Tower; no, I’m picturing something more exotic. Instead of the rather ordinary material Devils Tower is made out of, why not red rock, similar to southern Utah or even Mars? Indeed, why not red glass, glass of course often being of volcanic origin and present on Earth, but on Cerberus it might be absolutely dominant. Supplement it with black glass too, which is also of volcanic origin.
Since there’s no rain to erode it away, the glass shards that erode away from the wind would form vast fields of regolith-like sharp dust particles, the plateaus being dominated by wind-blown dune fields, only instead of sand it’s razor-sharp red and black glass particles that sparkle under the light of every star.
Despite the lack of precipitation, winds and storms could be extreme on this world: the sheer geography sees to that. With drops of up to 60,000 feet being commonplace, and daily ranges being extremely wide, cold dense air would pool in the interiors every night as temperatures dropped by over 100 degrees, air that would rush down the sheer cliffs of the coast, the katabatic winds amassing truly extreme velocities. Several hundred miles per hour would be routine: in some slot-canyon-like formations deep down near sea level, wind speeds could easily reach supersonic flow. These nightly winds, and the razor-sharp shards they’d carry down with them to the sea, would polish the bases of these creepy towers like cut gemstones, perhaps forming smooth mirrored surfaces of red and black volcanic glass. Think something like Antelope Canyon, but glassier.
These katabatic winds could scour the ocean waters out from the coast, creating regular standing waves, and interacting as they propagated across the planet to form rogue waves, which would be very common worldwide; indeed, with such extreme winds, it seems likely Cerberus’s oceans would have extreme wave action in general compared to Earth’s seas. Perhaps turning it into a surfer’s paradise.
This surfer’s-paradise image would be underlined by the fact that these glassy dust storms would create ample deposits of material along the shoreline, with waves polishing these razor-sharp particles into something more like our very own beach glass. Likely a very inviting and forgiving surface for a human being to walk on. Between wave and tide Cerberus wouldn’t present any forgiving land environment for a surface colony; the beaches are too inundated regularly, and the high plateaus are unbreathable, little better than vacuum, and in any case dominated by razor-sharp storms of glassy particles blown in from the dunes. No, space colonists, if they desired a permanent homestead, would likely live inside the sheer cliffs of the Devils-Tower-like mountains, close to the beach but at a safe vertical distance away from the waves, inside cracks (either natural or artificially made), perhaps accessing the ever-enticing beaches with the use of ladders. Much like whatever alien life dwells there locally, it would be an entirely vertically-oriented lifestyle, unlike anything found on Earth.
And considering how Thalassa, the first world colonized by humans outside our solar system of origin, lacks any solid surface (with even the liquid surface having an atmosphere far too thick to breathe), Cerberus would present a first: the first world ever settled by humans who can breathe on terra firma. It’s marginal, yes, and alien, but in the universe of my stories, once it’s reached it would be the closest yet to realizing the science-fictional dream of standing on an alien planet, without a spacesuit, and planting a flag on your new home. Thalassa might have been the site of first contact with an alien intelligence, but Cerberus would have draws all its own.
What would it be like, orbiting Sirius? Indeed, Cerberus might not orbit Sirius A at all, but rather Sirius B, its white dwarf companion. Yes, it’s more exotic and perhaps less likely, but planets are known to have formed around white dwarf stars and neutron stars, in the most extreme of conditions. It’s possible. Alternatively, Cerberus might have been captured by Sirius B (perhaps it was originally from Sirius A, or even another solar system altogether).
An orbit around Sirius B has the advantage of Sirius A appearing as a very bright star in the sky (much brighter than Venus does to us), which underlines the alien nature of this world’s sky. A world orbiting around Sirius A, by contrast, would see Sirius B be considerably less spectacular in the night sky. In any case, either Sirius A or Sirius B would be much bluer suns than our own…and much younger suns.
At only a few hundred million years old, there arguably would be insufficient time for complex life to have evolved naturally…but maybe that’s part of the mystique of this world. After all, we don’t really know if Earth really needed all those billions of years to develop a biosphere as complex as what we see today; perhaps, especially under the influence of a higher-radiation environment (which pumps mutations), life could evolve faster than it did on our world.
I’m considering also making Cerberus a moon rather than a primary planet: if Cerberus orbits a gas giant world, it could have a large looming companion in the sky. Make this companion have rings a la Saturn and it becomes even more science-fictional in the most cinematic way…especially if Cerberus has a highly inclined orbit around its primary, enabling it to see the rings face-on instead of edge-on. A chaotic origin of the system would make this setup considerably more likely.
It also has the advantage of avoiding tidal locking; around Sirius B any Earth-like planet would quickly become tidally locked to its sun, thus giving it a permanent day side and a permanent night side…which would be cool, but it’s a motif I already explored with Thalassa, over in Proxima Centauri’s system! So enough of that. Even the more exotic 3:2 tidal locks exhibited by a planet like Mercury would still give Cerberus a very long day and night, when the idea of this desert planet is there’s a very high daily range despite it having a rather Earth-like day length. So the only way to square the circle here is to have Cerberus orbit a primary and be tidally locked to it. Or for there to have not been enough time in its geological history for tidal locking to have occurred yet. But I think I’ll go with the motif of Cerberus actually being a moon: again, it’s science-fictional in the most cinematic way (how many iconic “planets” have actually been moons?).
As for the actual colonization attempt, the expedition to Thalassa took 20 years to reach its destination, launching from Earth at 21% the speed of light. As of when it launched in the 2040s (this is an alternate timeline that diverges in 1900), that was the state of the art, stacking solar sails, magnetic sails, and nuclear pulse propulsion, all functioning near their theoretical limits. And Thalassa was Earth’s first manned interstellar expedition. Probes were sent out as early as the 1990s, but back then 10% the speed of light was the state of the art, so even Alpha Centauri was only reached by around 2040.
In “Heart of Proxima” a fleet returns from Thalassa to much fanfare circa 2100; the original plan was 20 years in transit there, 20 years on-site, and those who wished to return could do a 20-year stint back. With Proxima Centauri’s distance, a full cycle would take 60 years, just enough for an individual human being to realistically expect to venture to another star, live there, and return to the homeworld to tell the tale.
No such luck for Cerberus, at least at the speeds attained by the Thalassa Expedition: at 8.6 light-years, a starship traveling at 21% the speed of light would take 41 years to reach Sirius. Realistically nobody is coming back from that trip (though already Proxima Centauri is far enough in this universe that one shouldn’t count on returning).
When would an expedition leave for Cerberus? Thalassa’s fleet left with much fanfare, and it was the first; we also don’t hear of any other interstellar expeditions even in 2100…but that doesn’t mean that they weren’t active, just that they weren’t as relevant as Thalassa’s. Which would only make sense. Even if we suppose that the Cerberus Expedition left, say, in 2050, only a few years after Thalassa’s, a 41-year journey means they’d only arrive in 2091. And the 9-year light-speed lag means that Earth would just be hearing back from them about their arrival in 2100, around the same time the Thalassan “Old Fleet” returns! So perhaps the reason we don’t hear about them in “Heart of Proxima” is because news of their arrival hasn’t even broke yet!
That opens up a few possibilities for pushing my sci-fi universe deeper into the 22nd century.
In particular, I’ve been toying with the possibility of alien artifacts…or at least hints of them. After all, Sirius is such a prominent star in our galactic neighborhood, and these bright points of light might act as cosmic beacons, drawing in curious visitors, perhaps enticing them to leave their mark in hopes that others like themselves might also be attracted to these easily-visible places that tug at the primordial imagination, to all those who look up at the sky and wonder “are we alone?”. What form might these artifacts take? Carvings in the spires of glass on Cerberus are among the possibilities: imagine images like in ancient Egypt being carved in these enormous sentinels of stone, only of alien origin. Or would it be too obvious?
After all, to discover such a blatant sign of advanced alien civilization in only the second habitable planet humans colonize would not be in keeping with the atmospherics and vibe of my sci-fi setting. Space is big; really, really big. And the civilizations who advance millions of years ahead of us and make it truly far don’t leave any obvious traces (this includes humans, once we fast-forward to just a thousand years into the future).
Alternatively, perhaps there’s yet another alien intelligence at work? Already the Thalassans have a civilization of sorts, and there’s even alien intelligence in the oceans of Enceladus, much closer at home, that’s non-technological (at least at first glance…). Why not on Cerberus too? One thought that occurs to me time and again is the possibility of space-dwelling life-forms; solar sail calculations show trajectories that pass by Sirius get a boost owing to its greater luminosity and gravity compared to lesser stars, so perhaps there’s some form of life that escaped to space (or evolved in space in the first place) and takes advantage (or, per panspermia, took advantage and was drawn toward its light, and seeded a world like Cerberus in orbit…). If Cerberus orbits a primary planet, said primary planet is likely a gas giant dominated by water clouds, just the sort of environment where life might arise and flourish on a world without a solid surface; perhaps, against all odds, there’s an alien ecology and intelligence there? Or even in both of these worlds, with their cultures in contact in ways not readily apparent to human outsiders?
I don’t know, I’m just brainstorming here. Another brainstorm is the idea of tornado-like phenomena being common on this world; after all, the katabatic winds would no doubt form twists, turns, and vortices on their way down, a perfect recipe for tornadogenesis. It might or might be host to alien intelligence, but to any human colonists, it would be a fierce world indeed, but one with undeniable beauty, and, despite the myriad advantages Thalassa might have on paper, the most enticing of all worlds man has encountered to date, urging colonists of the 22nd century onward to new adventures, as the next stars out from Sirius start to look all the more tantalizingly closer than they did on Earth…