Dyson sphere

A Dyson sphere is a hypothetical <a href="/facts/Megastructure/2JuASMeR">megastructure</a> that encompasses a <a href="/facts/Star/PFbd6ICx">star</a> and captures a large percentage of its <a href="/facts/Solar_power/NpgmEbU2">power output</a>. The concept is a <a href="/facts/Thought_experiment/GXlr0lz9">thought experiment</a> that attempts to imagine how a <a href="/facts/Spacefaring/zPrnATzo">spacefaring</a> civilization would meet its energy requirements once those requirements exceed what can be generated from the home planet's resources alone. Because only a tiny fraction of a star's energy emissions reaches the surface of any orbiting <a href="/facts/Planet/rbPjE6Bx">planet</a>, building structures encircling a star would enable a <a href="/facts/Civilization/xvGpjDPj">civilization</a> to harvest far more energy.
The first modern imagining of such a structure was by <a href="/facts/Olaf_Stapledon/10z2ssgF">Olaf Stapledon</a> in his science fiction novel <a href="/facts/Star_Maker/xBkGHTpB">Star Maker</a> (1937). The concept was later explored by the physicist <a href="/facts/Freeman_Dyson/kSRxTh2r">Freeman Dyson</a> in his 1960 paper "Search for Artificial Stellar Sources of <a href="/facts/Infrared_Radiation/44XdJNcc">Infrared Radiation</a>". Dyson speculated that such structures would be the logical consequence of the escalating energy needs of a technological civilization and would be a necessity for its long-term survival. A signature of such spheres detected in astronomical searches would be an indicator of <a href="/facts/Extraterrestrial_intelligence/X1c45DNV">extraterrestrial intelligence</a>.
Since Dyson's paper, many variant designs involving an artificial structure or series of structures to encompass a star have been proposed in <a href="/facts/Exploratory_engineering/GCLdQ5Rj">exploratory engineering</a> or described in <a href="/facts/Science_fiction/d9hE2Lwt">science fiction</a>, often under the name "Dyson sphere". Fictional depictions often describe a solid shell of <a href="/facts/Matter/osyc04UN">matter</a> enclosing a star – an arrangement considered by Dyson himself to be impossible.

Dyson sphere open-in-new

Dyson sphere