an artificial structure in the form of a hollow shell surrounding a star, built esp. in order to capture the star’s energy output
The Ringworld is a compromise, an engineering compromise between a Dyson sphere and a normal planet. Dyson was one of the ancient natural philosophers, pre-Belt, almost pre-atomic. He pointed out that a civilization is limited by the energy available to it. The way for the human race to use all the energy within its reach, he said, is to build a spherical shell around the sun and trap every ray of sunlight.
But there’s more to a Dyson sphere than collecting solar power. Say you make the sphere one astronomical unit in radius. You've got to clear out the solar system anyway, so you use all the solar planets in the construction. That gives you a shell of, say, chrome steel a few yards thick. Now you put gravity generators all over the shell. You'd have a surface area a billion times as big as the Earth’s surface. A trillion people could wander all their lives without ever meeting one another.
I thought that’s where you might be heading. A Dyson sphere.
Bob Shaw’s Orbitsville, which also was based on Dyson’s speculations about advanced civilizations converting planetary matter into a sphere about a sun and utilizing all that star’s energy and all the converted planet’s area as living space was not as spectacularly popular as Ringworld but kept the concept of the Dyson sphere at the center of the novel.
The same episode will also feature breath-taking footage of the Dyson Sphere, an effect meant to replicate a device two hundred million miles in diameter that was built around the sun of a now vanished alien race.
Through the square window: the armillary sphere of Tesler-Thano’s legalwares; a solar system of nested Dyson spheres, dark and lightless, slowly turning.
One must think about the physical possibilities of a Dyson Sphere habitat, to the point where one can see the implications for life on the inner surface.
The simple Dyson sphere concept missed an essential geometric requirement of a stellar enclosure.
For the first time, the Dyson sphere really did look like a planet. It was as small as Earth now, and growing smaller with each passing second. The instruments suggested that it did not exist at all, except visually.
Why anyone would create such an artefact in the first place was beyond him. It lacked the practicality of a Dyson sphere or a Niven ring.
Dismantle the moon! Dismantle Mars! Build masses of free-flying nanocomputing processor nodes exchanging data via laser link, each layer running off the waste heat of the next one in. Matrioshka brains, Russian doll Dyson spheres the size of solar systems. Teach dumb matter to do the Turing boogie!
This particular fragment of the nascent, fully enclosing Dyson sphere was diamond-shaped, 160,000 miles long and 100,000 wide.
Larry Niven, Ringworld
Michael Simons provided a link to the Dyson sphere FAQ, which mentions Freeman Dyson's article "Search for Artificial Stellar Sources of Infrared Radiation" in 1959 in Science as the original source. Jeff Prucher located a copy of this article and found that the term "Dyson sphere" does not appear there, nor does it appear in the correspondence that subsequently appeared in the letter column of the magazine.
Last modified 2022-02-01 14:07:06
In the compilation of some entries, HDSF has drawn extensively on corresponding entries in OED.