Ringworld

I myself have dreamed up an intermediate step between Dyson spheres and planets. Build a ring 93 million miles in radiusone Earth orbitwhich would make it 600 million miles long. If we have the mass of Jupiter to work with, and if we make it a million miles wide, we get a thickness of about a thousand meters. The Ringworld would thus be much sturdier than a Dyson sphere. Larry Niven