Dyson sphere facts for kids

A Dyson sphere is an idea about a structure that surrounds a star, first thought up by physicist Freeman Dyson, and then used in some science fiction works.

The idea of the Dyson sphere was the result of a thought experiment. Dyson noted that civilizations constantly increased their need for energy. He reasoned that as human civilization went on, there would come a time when it demanded more energy than the Earth could provide.

He proposed a system of structures designed to intercept and collect all energy produced by the Sun. Dyson's proposal did not detail how such a system would be constructed. His 1960 paper "Search for artificial stellar sources of infra-red radiation", in the journal Science, was the first to present the concept of the Dyson sphere.

There are at least three types of Dyson spheres:

1. A Dyson shell that is a solid structure and the inside could even become habitable if the sphere produces artificial gravity by spinning on itself. It would be extremely difficult, if not impossible to build (particularly because of the enormous quantity of material needed, the instability of the sphere and the strong gravity of the star affecting the whole structure).
2. A Dyson swarm, which is not exactly a sphere, but millions of smaller bodies orbiting the star and thus forming a more or less spherical structure around it. The most physically realistic structure to build.
3. A Dyson bubble that is made up of small bodies (like a Dyson swarm), but linked together with an extremely light and thin (but very large) structure such as a light sail around a star that keeps it centered because of stellar winds.

Images for kids

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  3D rendering of a Dyson sphere utilizing large, orbiting panels

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  Freeman Dyson in 2005

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  A Dyson ring—the simplest form of the Dyson swarm—to scale. Orbit is 1 AU in radius, collectors are 1.0×10⁷ km in diameter (10 Gm or ≈25 times the Earth–Moon distance), spaced 3 degrees from center to center around the orbital circle.

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  A relatively simple arrangement of multiple Dyson rings of the type pictured above, to form a more complex Dyson swarm. Rings' orbital radii are spaced 1.5×10⁷ km with regard to one another, but average orbital radius is still 1 AU. Rings are rotated 15 degrees relative to one another, around a common axis of rotation.

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  A Dyson bubble: an arrangement of statites around a star, in a non-orbital pattern. As long as a satellite has an unobstructed line-of-sight to its star, it can hover at any point in space near its star. This relatively simple arrangement is only one of an infinite number of possible statite configurations, and is meant as a contrast for a Dyson swarm only. Statites are pictured as the same size as the collectors pictured above, and arranged at a uniform 1 AU distance from the star.

See also

In Spanish: Esfera de Dyson para niños