At long last, our dome has a cover:
It’s made of 100 triangles of white cotton, each with magnets sewn into each corner, so that you can just stick it in place ting-ting-ting to the bolts.
Of course, sewing next to a magnet is physically impossible, because it magnetises the business parts of the sewing machine and causes it to jam. So instead, each corner is sewn without a magnet in it, and the magnet is pushed in before the threads are tied together. Doing this 300 times is incredibly boring (hence the ten-month project duration). If we ever need another dome cover, I’m outsourcing it to China.
Our house gets really cold over the winter, so I am seriously considering moving my office into the dome (adding some throws over the top for more insulation, and borrowing the bitcoin mine for warmth*). I should probably make a door first, though.