It has long been assumed that alien civilizations, if they exist, are far more advanced than humanity. A team of international researchers from Sweden, India, the US, and the UK has devised a method to search for advanced extraterrestrial megastructures, known as Dyson spheres.
Dyson spheres, proposed by physicist Freeman J. Dyson in 1960, are hypothetical constructions that could harness the energy of an entire star to meet the energy needs of a technologically advanced civilization.
The scientists, led by Matías Suazo of Uppsala University, utilized data from the European Space Agency's Gaia map of stars, the 2MASS infrared astronomical survey, and NASA's WISE infrared space telescope to search for Dyson spheres.
By investigating around five million sources, the researchers created a catalogue of potential Dyson spheres, focusing on identifying objects that emit excess infrared radiation, which could indicate a partially completed Dyson sphere.
They developed a specialized pipeline to filter out natural objects that also emit infrared radiation, such as nebulae and background galaxies, narrowing the list to 368 sources.
After further filtering, considering factors like H-alpha emissions, optical variability, and astrometry, the researchers reduced the list to seven potential Dyson spheres.
These seven candidates are identified as M-type (red dwarf) stars, which makes the presence of warm debris disks a possible alternative explanation for the infrared excess unlikely.
The team emphasizes that follow-up optical spectroscopy is necessary to better understand these sources and confirm whether they could indeed be Dyson spheres.