The great space station Helena was the largest construction of the human race in space. All the navies of the different nations had their own space stations, but none were as large or located as far on the edge of the security zone as Helena.
By observing from afar the rays of light reflected from the nearest star on the space base, anyone could confuse it with a satellite or a planetoid. But it was when you got closer that you could see how this engineering work that took a hundred years to build and that had only been fully operational for twenty years, stood out in the empty space.
The central spherical core had the radius of a small satellite; in it were the food, water, and oxygen production systems. Inside, various domes of artificial atmosphere allowed production and extension comparable to those of a small country; most of it was even dedicated to research and not direct production.