Dyson sphere

A Dyson sphere is a hypothetical megastructure that completely encompasses a star and captures most or all of its power output. The concept was first described by Olaf Stapledon in his science fiction novel, Star Maker (1937), and later popularized by Freeman Dyson in his 1960 paper, "Search for Artificial Stellar Sources of Infrared Radiation". 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. He proposed that searching for such structures could lead to the detection of advanced, intelligent extraterrestrial life. Different types of Dyson spheres and their energy-harvesting ability would correspond to levels of technological advancement on the Kardashev scale.