Free 2312 by Kim Stanley Robinson

belts that it was never going to be occupied at all except by a few small hardened scientific stations. Europa, a big beautiful ice moon, had a great depth of ice for people to delve into to escape the Jovianradiation, strong even there: wondrous ice palaces, with giant Jupiter always gnarling overhead—or everyone had thought at first. But it hadn’t happened, because there had proved to be aliens living in the ocean below, a complete ecology of algae, chemotrophs, lithotrophs, methanogens, scrapers, suckers, fans, scavengers, and detrivores, all swimming or crawling or holding on or burrowing in; and they created a problem. Some thought they had already contaminated this ocean by their exploratory intrusion into it, because examining it with a drill had been the Lake Vostok problem writ large. But they had done their best to sterilize the probes, and then, having discovered and sampled the full ecology, they had sealed off the hole, and now sat on the surface in scientific stations, culturing and studying their sample populations and pondering whether they should stay or go, and if they stayed, what kind of presence they should have. Possibly the proposed ice palaces would be perfectly fine, with the life below completely sequestered by the ten kilometers of glaciosphere that lay between the moon’s surface and its ocean. On the other hand, life being life, spermatozoically wriggling into every place it could reach, contamination might almost certainly be assumed to follow any occupation of the moon. And yet, given that these creatures appeared to be cousins of theirs anyway, long separated by meteor voyage—and now already recontaminated by a visit—would living above them and continuing to be a minor contaminant clearly be such a bad thing? When there were already people out there swallowing the alien microscopic life, and shooting it into their veins? And when life had been bouncing around the solar system and interacting with its cousins all along? These were open questions, interesting and vivid to the Europans and the other Jovians, less so to the rest of the system. Swan remained somewhat interested from her design days, and she approved their recent decision to go ahead and settle Europa, only perching unobtrusively on top of the internal indigenous aquaria.
    Now she spent her time walking the High Road that ran all the way round the Fourth Circle of Valhalla, waiting for their flight to Io. She was still avoiding Wahram, who watched her these days with a look of alarmed concern that she could not stand. Jupiter overhead was its usual lurid magnificence. Possibly the Jovians were right to be so self-absorbed; they had a whole little solar system here, full of different things. Between the rings of the crater, the surface of Callisto was a vast knobbly white plain, and Jupiter and the three other moons were up there performing their dance. It was a gorgeous space.
    But they were here to see Wang, so soon she grew impatient for the Io shuttle, and tired of the view overhead. Jove squiggling its buffooneries over and over—it was not art but chemistry, mere fractal repetition. The saving grace was that they had recently lit great gas lamps in the upper Jovian atmosphere, to better illuminate the towns located on the Galileans’ Jovian sides. One could see how these painfully brilliant diamond points were distorting Jupiter’s cloud tops, adding new swirls and eddies; that made it art, the whole thing a kind of mad goldsworthy.
    Finally the time came for the shuttle to Io.
    Swan said, “Pauline, are you going to be all right down there?”
    “I will be if you are. You definitely need to stay inside the Faraday cage there to stay safe. The Jovians will no doubt tell you that.”
    And during the trip they did, at great length. In a box inside a box, like Russian dolls: they were so proud. Down then to Io, shedding a furious aurora behind their spacecraft, a blaze of transparent blue and green electric banners and