And I thought the idea behind a Dyson sphere was to harness all power of a star by covering it fully. It's a nice idea for a science-fiction story but in reality it's just a dream.
A rigid shell or even just a lattice work would fail because of the polar regions can not be held in place by centrifugal forces. It would just collapse down and twist apart as it got close to the star and the orbital velocities start to differ between parts of the shell.
The only thing that might hold up for a while is a ring around the star but a big problem is to keep the atmosphere in place. Walls over 100 km high would still loose atmosphere at a high rate and it would be quite the challenge to build... So a tube is the logical solution and we end up with a Dyson doughnut.
Well, metal is common but nitrogen and oxygen is also quite nice to have inside our doughnut. I think the Earthlings would be pissed off if we took their atmosphere, at least in the beginning.
https://xkcd.com/681/
But I think we are getting a bit off topic now.
/Göran
A rigid shell or even just a lattice work would fail because of the polar regions can not be held in place by centrifugal forces. It would just collapse down and twist apart as it got close to the star and the orbital velocities start to differ between parts of the shell.
The only thing that might hold up for a while is a ring around the star but a big problem is to keep the atmosphere in place. Walls over 100 km high would still loose atmosphere at a high rate and it would be quite the challenge to build... So a tube is the logical solution and we end up with a Dyson doughnut.
Well, metal is common but nitrogen and oxygen is also quite nice to have inside our doughnut. I think the Earthlings would be pissed off if we took their atmosphere, at least in the beginning.
https://xkcd.com/681/
But I think we are getting a bit off topic now.
/Göran