Dyson's original concept was basically to completely obscure the star in a cloud of satellites. It would be a little inefficient, insofar as some satellites wo

Dyson's original concept was basically to completely obscure the star in a cloud of satellites. It would be a little inefficient, insofar as some satellites would obscure others at any given time, but it's at least physically possible. There's been some speculation that the integrity of a Dyson shell (the thing most people know as a Dyson sphere) could be maintained by basically running large masses in orbits along the shell. Again, it would be a little inefficient (you're using some of the star's energy to power "not collapsing"), but we don't necessarily know it's impossible.