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Dyson Spheres Around White and Red Dwarfs: Calculating the Search ⚡ экспресс

Original: "Dyson spheres on H-R diagram"
· Amirnezam Amiri
arXiv:2602.23270 · 2026-02-26 · CC BY 4.0 · ⏱ 1 min · Stellar Galaxies
Scientists have calculated how giant 'blankets' around stars — Dyson spheres — would glow, to help telescopes find traces of aliens.
Abstract

Picture a sphere that catches all the light from a star. Scientists have figured out that if you build one around a dim white or red dwarf, it would be invisible to the naked eye, but would give itself away with a faint heat glow in the infrared. Will we ever spot something like that through a telescope?

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If you build a giant blanket around a star, you get a Dyson sphere. It absorbs all the radiation and glows in invisible heat rays. No such sphere has been seen yet, but astronomers know: to find it, look for this thermal glow.

Scientists have calculated how the blanket heats up around two types of stars: white dwarfs (cooled-down remnants of suns, whose nature was first described by Chandrasekhar) and red M-dwarfs (the most common, cool stars). The larger the blanket's radius, the cooler it is — this follows from the law discovered by Planck. An unexpected conclusion: near a dim white dwarf, the blanket will heat up more but glow faintly, while around a bright red dwarf, it will remain barely warm, yet shine with full power.

This can be detected with the James Webb Space Telescope: a Dyson sphere doesn't hide the star, it only shifts its light into infrared — invisible heat, discovered by Herschel. Methods of brightness measurement and spectral analysis will help spot these strange objects and, perhaps, find traces of extraterrestrial intelligence.

🎯 If you built a Dyson sphere around the Sun at the distance of Earth's orbit, its surface would have room temperature — about 300 K.

🎬 Giant spheres around stars have appeared many times in science fiction, for example, in the series 'Star Trek: The Next Generation' (episode 'Relics').

T \propto R_D^{-1/2}
The temperature of the sphere drops inversely proportional to the square root of its radius.
Scientists
Christian DopplerD. B. McLaughlinDidier QuelozMichel MayorR. A. RossiterAlbert Einstein
Tags
photometry spectroscopy JWST
Laws
Doppler effectgravitational lensingMaxwell's equationsPlanck's lawPlanck–Einstein relationWien's displacement law
Original: arXiv:2602.23270 · CC BY 4.0 · bridge42worlds