High Quality Content by WIKIPEDIA articles! A Dyson sphere is a hypothetical megastructure originally described by Freeman Dyson. Such a "sphere" would be a system of orbiting solar power satellites meant to completely encompass a star and capture most or all of its energy output. Dyson speculated that such structures would be the logical consequence of the long-term survival and escalating energy needs of a technological civilization (regardless of the effects of planetary warming caused by the input of energy to the planet), and proposed that searching for evidence of the existence of such structures might lead to the detection of advanced intelligent extraterrestrial life.