The Horizon System: Riftia, in the Shadow of the Sun
An unearthly beauty like an angel of Celestia
Yet a storm of horror bringing ruin to all
A unique existence, impressed in memoria
Yet an unfathomable copy, time in its thrall
A humble servant, a friend, a ‘human’
Yet an existence beyond gods eternal
With honor, valor, bonds pedestrian
Yet a bringer of death always infernal
Savior, Conqueror, Mother of Monsters
Who are you, great Face of Horizon?
- Inquiry into the Archon of the Outer Expanse, ‘Atropa’ [Endless Rain Upon Viridian Skies]
Riftia (Warm Marine Superterra, Planet)
System - Horizon-Actinophrys
Mass - 2.665 Earths
Radius - 8,059 kilometers (1.260 Earths)
Global Average Temperature - 152.1°C
Day Length - 11h 35m 10.2s
Year Length - 1.161 years
Number of Satellites - 19
ESI - 0.667
Etymology - From the Giant Tube Worm Riftia pachyptila, for its ability to survive and thrive in harsh, volcanic environments through great evolutionary ingenuity.
Overview
From the wonderful chaos of the Resonant Worlds comes the golden, asteroid-spangled giant of Riftia, a massive, pressurized hothouse perched on the edge of destruction. With an average surface temperature of 150°C, we might expect Riftia to be a baked-dry desert like Venus or at the very most an inhospitable acid world like Tridacna or Navanax. But Riftia cares not for such preconceptions.
Instead of sun-bleached sands and barren lavas, Riftia’s surface is immersed in great seas of hot, salty water out of which reach jagged fingers of igneous rock bound with stromatolite mountains. Though its surface has fallen into a moist greenhouse, the aggressive removal of carbon dioxide and water vapor by an atmospheric ecosystem has prevented the planet from becoming inimically hot. Thick hazes of volcanic gas or floral spores and unbroken clouds of water vapor efficiently reflect heat away from the planet, while its heavy gravity prevents water from escaping and turning it into a desert. Though the equatorial summer can push 200°C, Riftia’s nitrogen-dominated atmosphere is twice as thick as Venus’s, forcing the boiling point of water to nearly 300 degrees.
This world might seem like purgatory to us. But for millions of species of strange Riftian life, it is home sweet home.
Lifeforms
Suffocating, cloying, humid heat is the rule on Riftia. Though the oceans do not completely evaporate, the lowlands simmer with hot vapor thick enough to cook and steam the corpses of aerial creatures falling from above. Even if the heat wasn’t enough to kill, there is so much water in the air that one would drown as their lungs filled with condensing dew. And even if all those issues were sidestepped, the air is so thick with hydrogen sulphide and sulphur dioxide that a human would be fatally poisoned in seconds. And yet, this antediluvian hell is as thick with biological activity as the rainforests of Horizon or the reefs of Panthalassa.
A parallel biosphere of prokaryotes survives the extreme heat of the oceans and lowland plains with an exotic genetic code fashioned from a propylene glycol backbone highly resistant to extreme temperatures. Though they cannot survive below 80°C or so, their biological processes are supercharged by high temperatures and so they grow, reproduce, and adapt far faster than most other life. ‘Rainforests’ of thorny, silica-spiked biofilms grow wherever there is moisture (i.e. everywhere), breathing in hydrogen sulphide and using what little sunlight pierces through the clouds of sky algae and spores to grow. In the absence of competitors, highly complex multicellular prokaryotes are a common sight, from roving packs of myxobacteria-like slime molds to metamorphic bacterial fish and amphibians to lumbering, reptile-like swamp-dwellers. Though all are ectotherms, warm blood being useless at a toasty 150°C, many are active and intelligent animals that are in no way brutish and primitive as the hazy fog of Deep Time might suggest.
At higher elevations, dropping temperatures make life possible with conventional biochemistry. The thermophiles of the lowlands disappear, giving way to ‘steam forests’ of heat-resistant eukaryote flora. Temperatures are low enough to accommodate familiar Horizonian fauna, but the thick, soupy air makes flying more like swimming. The radiator-trees, cochleophytes, and air kelp that carpet these sky-island mountaintops build ecosystems more like algal reefs than terrestrial forests. Though many fauna that inhabit these forests are drifters from the wider aerial ecosystem, there are plenty of native inhabitants as well; from echinoderm-like herbivores that gnaw at the bases of the algal trees to clinging jellies swinging through the branches to fluttering, slug-like fliers darting in and out of the writhing canopy. Roiling in the eternal storms of a super-Venusian giant, these dreamlike banks are unlike any other.
Rising beyond the montane steam forests we find a third and final stratum; the aeroplankton. Winged and ballooning organisms, both plant and animal, are abundant in the thick air, while clement temperatures allow lifeforms unadapted to high heat to survive. However, vital mineral nutrients like phosphorus and iron are not gases, so permanently airborne flora must find some way to obtain them. Some like the medusoid needleworts resort to carnivory in order to meet their needs, others feed on volcanic ash with long curtains of sticky tentacles or pumping filtering apparatuses, while yet others descend to the searing surface to pick minerals from the soil. The enormous floating reefs that they construct host millions of motile fauna species, from centipede-like skyfish to vulturine amphibians to filigree, draconic air serpents. Life in these skies is fierce and fast-paced; all manner of predators from swarming piranha-bats to cetaceous titanostomes ply the reefs while freezing updrafts and gouts of volcanic winds can vitrify or incinerate. Eventually, all life of the sky runs afoul of these hazards, falling from heaven to the damp hells beneath.
Past & Future
A billion years ago, Riftia was in the habitable zone. Though few preserved records of this time in its history remain, it very well could have been a true Earth analog, an ideal paradise for life like its sibling Changxing. With a single large moon, an orbit close to the inner edge of the habitable zone, and a nitrogen-dominated atmosphere, billion-years-ago Riftia may well have been the most Earth-like planet in the Horizon System. But today, Riftia is nothing like Earth.
As Actinophrys steadily brightened, Riftia exited the habitable zone. Increasingly warm surface conditions caused its oceans to evaporate, releasing huge amounts of water vapor into the atmosphere that proceeded to warm up the atmosphere even more. Over the span of some 100 million years, the atmosphere grew to over 300 times as thick as Earth’s while surface temperatures shot up to a hellish 1700°C, hotter than Chrysaora is today. Fortunately for the microbial life that existed on ancient Riftia, the thickening of the atmosphere made flight easy enough that a small contingent of them were able to escape the rapidly deteriorating surface to make a home in the sky.
Photosynthetic microbial aeroplankton removed huge quantities of water and carbon dioxide from the atmosphere just as volcanic activity was pumping out nitrogen to replace the losses. Over the next 400 million years, the surface solidified again and the reflective biological hazes eventually brought the atmosphere back below the boiling point of water, letting the seas rain back down to fill their vanished basins. Coincidentally, this miraculous recovery from a runaway greenhouse occurred just in time for multicellular life exiled from Horizon to chance upon the planet, newly habitable once more.
Civilization
Riftia was a source of endless fascination for Old Horizon, as frequent blooms of aeroplanktonic flora cause flashes of green, blue, and violet visible from across the system. Before the advent of the telescope these were usually attributed to supernatural intervention. However, this classical view of Riftia holds little influence on Horizon today. Modern views of the planet’s nature are more informed by pre-collapse scientific developments. During the planetary romance literary era of Horizon (from the discovery of life on Panthalassa to the first systematic robotic explorations of the other Resonant Worlds), authors often speculated about the existence of intelligent life advanced enough to change the color of its atmosphere as a means of communication. Even after the ‘Great Disappointment’ when the Riftian civilization failed to exist, renditions of this romantic fiction remained strong in popular culture. The vision of Riftia that has survived to the present is a mix of the real and the fantasy; most Horizonians today regard Riftia as a steaming, inhospitably hot realm, yet one nevertheless inhabited by erudite beings far superior to themselves.
The view of Riftia as an astral realm of hyper-advanced star people has historically led to some misunderstandings when Horizon’s recently-reacquired interstellar empire interfaces with its relict natives. But beyond that, the planet Riftia itself is also of great scientific and economic interest. In the biotechnology-dominated society of the resurgent Horizonian Empire, novel genetic sequences are always in high demand for cosmetic, industrial, and convenience modifications. Worlds like Riftia with great biodiversity and exotic biological systems are prized, both as sources of bio-mods and as a basis for more delicately engineered solutions. In a society where people wear faces like masks and the once-sacred temple of the body is viewed as but a blank canvas to mark with the expressions of one’s persona, worlds as strange as this are but challenges to match in sheer strangeness.
Whispers From the Reach
Hi everyone! Welcome to Introduction to Applied Xeno-Paleontology, class of 2229! We at the Xenobiology Department extend a warm invitation to our newest flock of test subjects lab interns, student researchers, and aspiring bioengineers! I’m your professor, 'Dr. Guanling’, and I’d like to start off with- yes, question?
…
Oh, I see. I suppose a bit of explanation is in order.
So, first things first - yes, I am the Archon of the Outer Expanse, or more precisely a large part of their personality matrix. Most of you should be familiar with me from your textbooks in Contemporary Galactic Geopolitics, while for our long-life students your parents probably talked about me when you were growing up. And yes, that does mean that I was the one who beat the Digital Gods of Sideros to scrap and turned the Anabantarian Infinite Empire into a haunted ruin.
…
Oh, you’re asking why I decided to work at a university instead of joining the Dread Hunt?
Well, contrary to what your textbooks may have told you, I don’t love war. Sure, I’ve earned my battle-maniac reputation and I do enjoy a good spar, but I have motives beyond bloodlust.
All of you should have read enough on Horizonian governance to know that the Emperor keeps us Archons on our leashes with the promise of our ultimate desires - our Original Visions. Though the exact details are confidential, I’ll be generous and tell you the focus of mine.
My focus is ‘Talent’.
In all my years of life, I have seen nothing more beautiful than the earnest pursuit of the Original Vision. From young Hyperion reaching for stars he can never see to grand Chrysiridia chasing away the evils of the Reach, every one of this universe’s titans started out as a determined hopeful just like you. We pushed our talents past their limits and broke over and over as we dared to dream of a different world. And through those dreams, those acts of resistance against the banal brutality of the Demise, we cut down the choking void of nihility and carved our bleeding signatures into the star-struck flesh of the Universe.
Though the sacrifice of your predecessors shields us from the full range of horrors the world has to offer, the promise of the Original Vision still slumbers within each and every one of you. It is my sincere hope that as you spend your next eight years with us chasing the mysteries of the Reach your own wildest dreams will begin to blossom. And who knows? Perhaps, as you hunt your promised ambitions, you will one day find your name engraved in the Universe alongside mine!
…
Well, we’ve spent enough time on me. Now then, open up your notebooks and let us journey to our first destination, the Early Erithohelian stratigraphic stage of Horizon…
Excerpt from Atropa’s first-day lecture for Introduction to Applied Xeno-Paleontology of the 2232-2233 academic year at the Amazonian Institute for the Arts and Sciences (AIAS).
While we usually imagine hive minds as unknowable, incomprehensible intelligences commanding myriad legions of faceless, mindless drones for incalculable nefarious agendas, the modern Horizonian Empire is a vibrant, varied counterexample to the supposed rule that hive minds must be alien horrors.
While many gestalt consciousnesses are aware only at the highest levels and maintain absolute control over their drones, Horizon’s Emperor is reserved with its authority. Outside existential emergency situations, subordinate gestalt patterns are permitted almost total autonomy, their choices being shaped only by the vaguest of suggestive influences. Those subordinate patterns, on the other hand, are given great liberties to choose how to use their drones - some dominate vast swarms of mindless husks, others split themselves into numerous subordinate identities coordinating their lives across tens of light-years, while yet others live freewheeling through the network, jumping from incarnation to incarnation as they seek all the universe has to offer. While the automated administrative and industrial belts of Horizon’s Glacial Midwaters can be just as soulless as a traditional hive, population centers like the Radiant Corridor and Outer Expanse are practically indistinguishable from the bustling metropolises of individualist species.
While the Emperor’s generosity permits the Horizonians to express individualist qualities, the effusion of culture that permeates the Empire cannot be the result of its sovereign’s meddling. No single individual, no matter how intelligent, could possibly replicate the minutiae of a whole civilization - especially one deprived of any sort of intelligent companionship for nearly a million years. Rather, the culture of modern Horizon owes its existence to the way its citizens reproduce.
Naturally evolved hive minds usually propagate themselves by sending dispersive breeder drones out of their territory to start new hives independently, while most artificial gestalts do not reproduce at all. The gestalt patterns of Horizon, on the other hand, replicate in a manner akin to budding; particularly powerful memories or personality aspects of a ‘parent’ pattern can gradually develop their own egos. The Emperor’s memories of its contemporaries and their descendants comprise some 90% of all living Horizonian gestalt patterns, and it is through their existence that the traditions of a civilization dead for as long as Old Horizon has been were revived. Though the accessory gestalt patterns that this budding produces are not ‘children’ in the traditional sense, they rarely have the full faculties of their progenitors - hence the need for institutions like AIAS.
