At first most of the greenhouse space was given over to growing soil itself. Soil as opposed to dirt was about 20 percent alive by weight, and plants were very much happier growing in it than they were in dirt like the valley’s dead loess. When they had viable soil, which fortunately grew in tanks filled with loess at nearly the speed of bacterial reproduction itself, they spread it in the greenhouses and planted crops. These were mostly fast bamboos at first, bamboos they had nursed throughout the long voyage to Tau Ceti without much needing them; now they came into their own, as they were a crucial building material, providing strong beams at a growth rate of a meter a day. Meanwhile the settlers’ food still came mostly from the ship and was flown down to them.

This created another supply problem. They had robot ferries capable of flying down from the ship to Aurora, then refueling and launching to get back up to the ship, but they needed fuel. One of the factories in the valley was entirely devoted to splitting water into oxygen and hydrogen, the main components of their rockets’ fuel. The factory itself had to be powered, however, and splitting water was very energy-intensive. They had two powerful nuclear reactors with them on the surface, providing 400 megawatts total, but the uranium and plutonium in the reactors would not last forever, and the ship’s supply was only adequate for the ship. Was there uranium on Aurora? According to standard theories of planetary formation, there had to be some; but the entire Tau Ceti system was less metallic than the solar system, and heavy metals only accumulated well on planetary bodies with a steady churn of tectonic action or tidal flexing. It wasn’t clear Aurora had ever had either, and given the uncertainty on this point, it was felt that they were going to have to devote a good deal of their manufacturing capability to building wind power generators on the burren. For sure there was going to be enough wind.

The people in the new settlement named it Hvalsey, after a town on the west coast of the Greenland on Earth. Quickly they expanded around the greenhouses. Stonecutters and foundries provided stone blocks and aluminum sheeting for construction, also glass windows for greenhouse roofs and walls. The city wall helped solve the wind problem. Some said Hvalsey looked like a little medieval walled town.

They were finding that the winds shifted in a somewhat predictable way through the course of the daymonths. When the air above a region was lit by Tau Ceti for nine days straight, it heated and rose, creating low pressures on the surface that cold air from the night side rushed in to fill. Then when sunset arrived, and a region was in night for nine days, it cooled down so drastically that snow and ice appeared on all the islands, and sea ice covered the calmer bays and reaches of the ocean, but not usually on the open sea, which was too buffeted by waves and wind to freeze over. The cold air in falling created pressures that shot out to the sides, filling the relative gap under the rising air on the sunlit side. So the winds were always swirling, mostly from night to day. Midday and midnight appeared to be the calmest times.

The long nights over the inner hemisphere never became quite as cold as those over the outer hemisphere, but they still dropped to well below freezing. If they were going to do agriculture in the open air, they were going to have to adapt their Terran plants from an annular to a monthly temporality. Watching their fast bamboo grow a meter a day, it seemed possible that they could engineer crops to grow to harvest in nine days, but no one could be sure how that would work, or even if it was possible. If they had to confine their agriculture entirely to greenhouses, it seemed like a fairly serious constraint. But they would cross that bridge when they built it, as Badim put it.

Meanwhile, in terms of the wind, which kept forcing itself to the forefront of their attention, the monthly air flows were regular, but not entirely consistent. They had a very sensitive dependence on conditions that were always changing. But as they learned more about Aurora’s weather, they began to identify certain patterns. One thing was perfectly obvious: on most days it was going to be windy.

Aurora  _3.jpg

E’s year was 169 Terran days long. The Auroran month, 17.96 Terran days long, therefore divided into the solar year of 169 days to create about 9.2 months a year, and thus the usual problem of trying to reconcile lunar months to solar years.

They did not worry about that now.

Aurora  _3.jpg

With the town walls under robotic construction, and the platting of the town finished and building sites being prepared, Euan frequently joined the teams going out to explore the sea valley. And he wanted to take off his helmet and breathe the ambient air.

This came as no surprise to Freya. The data from the monitoring stations were making it clear that Aurora’s atmosphere was breathable by humans, that indeed Aurora’s atmosphere was the most Earthlike aspect of their new home, and the main reason it scored so high in Earth analog rubrics. So as he joined all the scouting expeditions he could, Euan pushed harder and harder for official permission to take off his helmet. “It’s going to happen sooner or later,” he said. “Why not now? What’s keeping us from it? What are we afraid of?”

Of undetected toxins, of course. This was what he was told, and to Freya the caution was obvious and justified. Poisonous chemical combinations, unseen life-forms: the precautionary principle had to guide them. The Hvalsey council insisted on it, and also referred the question to the ship’s executive council, who said the same thing.

Euan and others of his opinion pointed out that their atmospheric and soil and rock studies had now gone right down to the nanometer level, and found nothing but the same volatiles they had detected from space, plus dust and fines as expected. The atmospheric gases were much like the air in the ship, except slightly less dense. Studies on the ground had confirmed the abiologic explanation for the oxygen in the atmosphere; they could even estimate its age, which was about 3.7 billion years. Tau Ceti, brighter then, had split Aurora’s hot ocean water into oxygen and hydrogen, and the hydrogen had escaped to space, leaving the oxygen behind. The chemical signatures of that action were unambiguous, a finding that had reassured the biology group that they did indeed have the place to themselves, as indicated by everything else they had seen.

Euan wanted to start that part of their new history, the first moment of going outdoors and breathing the open air. Freya said this to him during one of their conversations, and he replied, “Of course! I want to feel that big wind fill my lungs!”

The executive council continued to ignore the biology group and to refuse permission, to Euan or anyone else. Once the seal was broken between themselves and Aurora, there would be no going back. They needed to wait; to experiment on plants and animals first; to be patient; to be sure.

Freya wondered what Devi would have said about it, and asked Badim what he thought, but he only shook his head. “I’m not sure,” he said. “She was both cautious and bold. What she would say about this, I just don’t know.”

The executive council asked the security council to consider the matter and make a recommendation, and the security council asked Freya to join their meeting. Badim said the invitation was because of her friendship with Euan. The committee members were worried about him in particular.


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