The solar foundries of Dee are one of humanity’s most impressive technological achievements. A vast system of fusion reactors working modern-day alchemy powered and fueled by the sun, the foundries enabled the spread of earthly biospheres far and wide beyond Earth itself. <.p>
From the beginning, the primary goal of the whole gigaproject was phosphorus. That fifteenth element is plentiful on earth but quite rare everywhere else, and a bottleneck for life support systems. The Moonicipality, with a population of millions and always growing, was struggling to source it by the 300’s D.E., despite stringent waste recycling processes and a strong funerary culture built around the preservation of biomass. To introduce new phosphorus to the ecosystem they relied on imports from Earth, some of the only space launches from the old planet in that era. The shipments were costly and reliant on Earth’s wildly unstable geopolitics.
This was unsustainable, and the Moonicipality hatched a bold plan to source phosphorus independently: they would synthesize it by colliding lighter elements together using the power of the Sun. In 298 D.E. the Alchemical Guild was incorporated for this purpose. The master-planned city of Physicsburg on the far side of the moon quickly became a major center for the Guild’s research. There were particle accelerators and colliders spanning huge swaths of lunar surface, but these were only good for basic testing, and wouldn’t be sufficient to produce anything at an industrial scale. For production, they would need more energy and more raw material. They would have to get closer to the Sun.
In 315 D.E. the first of thousands of cargo flights from earth-moon L2 spaceport to Dee set off. A huge solar sail crewed by rats slowly lofted tons of construction equipment and instrumentation away from the mother world’s sphere of influence and towards the Sun. A legion of Alchemical Guild personnel would follow months later on faster ships.
First to be constructed were the orbital beaming arrays, vast mirrors that floated on photon pressure and focused sunlight onto the surface of Dee.
Then, an immense electromagnetic funnel to slurp helium ions from the sun into the first in a long chain of fusion reactors, the Helium-Hydrogen reactor. This reactor was mostly a proof of concept, and although it successfully produced lithium isotopes starting in 336 D.E., it never did so at scale.
Next, a helium-helium reactor was built along with upgrades to the funnel. It produced beryllium for space and industrial uses, but that was not its primary purpose - it was just a stepping stone towards synthesizing heavier elements.
After that, a pathfinder reactor was added to the chain to test what fusion processes were most scalable using the previous two reactors’ outputs. Helium-beryllium and lithium-lithium to produce carbon, beryllium-lithium to produce nitrogen, and beryllium-beryllium to produce oxygen. Two more pathfinder reactors were built to combine these products, successfully running test reactions all the way up to sulfur. It took years of fine-tuning, however, to produce stable isotopes, but by 349 D.E. a process for phosphorus production was finally ironed out.
All this development happened at a breakneck pace, with thousands of engineers and theoreticians employed moonside by the Guild and nearly ten thousand personnel on site at Dee working shifts around the clock. Dee, a tidally locked planet, knows no day or night, and neither did the scientists, engineers and tradespeople building and running the reactors there. Vast cities of tunnels spread beneath the blazing sunward surface, home to a culture that embraced material excess long before any other off-Earth society in the system ever could. The Guild had mysteriously deep pockets to finance its people’s lifestyles long before it ever began to produce phosphorus at scale. It was always unspoken, but the Moonicipality’s currency was backed by the risk of extinction.
After further expansion of the beaming array and funnel, two redundant chains of reactors were built to produce phosphorus at scale. First, helium-helium reactors, which fed intermediate-mass reactors to fuse the beryllium into stepping-stone elements, which were then combined into phosphorus. Finally, a stabilizing reactor turned the phosphorus into a useful, non-radioactive product. An attached facility packaged the material into waxy white cylinders and sent them up a space elevator to be shipped back to Moon, often by the very same solar sails that had brought the materials there to begin with. The first shipment departed in 361 D.E., and is widely seen as the moment that life truly slipped the surly bonds of Earth.
Progress down the periodic table slowed after that as the Moonicipality was not especially interested in anything much heavier. The pathfinder reactors were run only by a dedicated research team, without the vast engineering pool or capital budget it had enjoyed before. But the experimenters persisted, pushing the pathfinder reactors as far as Platinum before a confluence of disagreements and shortfalls essentially formed a barrier to further progress. Despite its name, no one in the generation that started the Alchemical Guild, nor their children, would ever see a nugget of synthetic gold.
By 400 D.E. there were four more redundant phosphorus reactor chains, and Dee’s population had exceeded ten million. Mass production of phosphorus supported a higher standard of living on the Moon and the Asteroids than ever, and enabled population booms around the outer planets. Following generations would take it for granted, but the generations that built the foundries took immense and deserved pride in their accomplishment.