Location: Inside boundary of galactic halo
Body Type: Cometary body
The object known as Snowflake, from the outside, looks like a delicate collection of frozen volatiles around a small core of rock, with the faintest wisps of gas hanging around it like a suggestion of an atmosphere. Aside from a single deep crater in one part of the snowball, the surface is a phantasmagoric wonderland of delicate icy shapes; feathery and delicate shapes blossom from the surface in a frigid and otherworldly jungle. From this exterior vantage, it looks like a beautiful but utterly mundane object, like one of millions in any Oort cloud in the galaxy.
Enter that deep pit, however, and pass through improbably effective airlocks to enter the false rock at the heart of the object; some unknown process keeps the interior heat from melting the surface ice, possibly relying on the Pandora Gate in the object’s heart to pump it away. Either way, Snowflake is what someone might design if they were looking to create a galactic-scale spying outpost – camouflaged perfectly as just another generic comet-in-waiting in deep freeze.
The interior, when Snowflake was discovered, was pumped full of argon gas and kept just warm enough to keep the interior pressurized. Since then, the atmosphere has been carefully stored and replaced with a familiar nitrogen-oxygen mix; the airlocks seem to have no trouble with this, managing to capture enough of the atmosphere that local space remains effectively uncontaminated.
Few clues exist as to who the original builders of Snowflake were, other than their practical engineering being advanced even by the standards of the nanotech era. The shell seems to be some carbon-based metamaterial that serves as a nearly perfect insulator, with almost no heat transfer to the snowball outside.
Of interest outside is a system that shows signs of having been inhabited recently enough that the habitable-zone world has a heavily polluted atmosphere; heavy concentrations of greenhouse gas and manufactured compounds saturate the atmosphere of what was probably once a nice terrestrial planet. Now the oceans are almost too acidic to support life, any signs of glaciation are gone, and a massive die-off seems to be underway if the swelling levels of methane are any indication. Two small ion drive probes have been dispatched on long trajectories that will get them into orbit within the next few decades; while an antimatter courier could make the trip faster, the risk of lingering traces of the fallen civilization picking up on it was deemed too dangerous.
Firewall, for their part, have been in the thick of it since the system was discovered; their in-place sentinel is the one who argued the argonaut research team into sending probes on oblique trajectories, and the one who ensures that discipline is maintained with the airlocks and thermal signatures. The conservatives of Firewall regard Snowflake as a long-range mousetrap waiting to be perturbed, and attempted to argue against even disturbing the argon atmosphere and chill environment of the quasi-habitat. So far nothing has happened to justify their concerns, but the dying world in the system has helped sustain their points.
Curiously, despite the evidence of heavy industrialization on the planet, no evidence can be found of space-faring capability in the system at large, nor any sign of automated radio signals. This, too, has helped fuel the arguments of the conservatives, both the Firewall plant and the more cautious of the argonauts. Were transhumanity to go extinct tomorrow, the Sol system would be noisy for centuries or millennia yet, but the system that Snowflake is in is deathly quiet. Proposed explanations have included a sapient species that can “hear” the radio spectrum, who wouldn’t want to pollute their living space with extraneous noise; a TITAN-style outbreak that simply ate itself; and a sapient race that lacked the needed curiosity to look up at the sky and wonder what lay beyond the atmosphere.
Due to the low-profile presence in the system, no one is yet aware that the system is, as a whole, curiously depleted; none of the expected gravitational resonance points hold any asteroids, no active or burned-out comets orbit within ten AU of the star, and even the Oort cloud is depopulated. It gives the impression that someone – likely long before the dying world hosted sapient life – someone aggressively stripped this system of useful resources outside of a gravity well and then departed. This knowledge would help explain the lack of spacefaring capacity to some degree, although mysteries would yet remain.