How many Dyson spheres could exist in our galaxy?

Scientists have recently discovered intriguing clues that suggest the possible presence of advanced alien technological structures around seven stars in our Milky Way. These Dyson spheres, as they are called, are hypothetical megastructures designed to harness the energy of their host star. While researchers cannot definitively confirm the presence of extraterrestrial civilizations, the discovery has captivated the attention of the scientific community, rekindling interest in the search for life beyond our solar system.

Closer to the stars

The innovative idea of ​​Dyson spheres was first put forward by theoretical physicist Freeman Dyson in 1960. This theory proposes that highly advanced extraterrestrial civilizations could one day build huge structures around their stars of origin or even around black holes in order to take advantage of the prodigious energy emitted by these celestial objects. This would provide these civilizations with colossal resources, thus paving the way for technological advances and spatial expansion on a scale previously unimaginable. However, Dyson spheres are not the only form that such megastructures could take. Less monumental versions could also be envisaged, such as ring stations orbiting a star or swarms of giant mirrors, all designed with the ultimate goal of capturing and efficiently exploiting stellar energy. This bold vision of the future of space exploration and the use of cosmic resources remains purely theoretical for now. However, the idea of ​​Dyson spheres continues to inspire scientists and authors of science fictionwhile fueling our imagination about the unexplored possibilities of the Universe and the forms of life and civilizations that could thrive there.

How to detect them?

Scientists express considerable confidence in their ability to detect the hypothetical Dyson spheres. Indeed, if such a megastructure were to surround a star, it would cause a significant emission of infrared radiation due to the heat emitted by the star trapped inside the sphere. This heat emission would then be detectable from Earth using astronomical observatories equipped with sensitive sensors. Technological advances in astronomy have indeed considerably improved our ability to observe and analyze the electromagnetic spectrum of stars and celestial objects. Space and ground-based telescopes, such as the James Webb Space Telescope and NASA’s Wide-field Infrared Survey Explorer (WISE), are specially equipped to detect and study these emissions.
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Several candidate stars

In a new study, researchers used a computer program to examine more than five million stars in the Milky Way, identifying seven potential candidates for Dyson spheres. These stars are all M-type dwarf starssmaller and darker than our Sun, located at less than 1,000 light years of the Earth. This discovery is not isolated. A study similar study had recently identified 53 potential candidates through data collected by different space observatories. The researchers took into account several factors that could lead to false positive results, but acknowledge that it is impossible to completely rule out other explanations, such as extreme debris disks. The next step will be to make follow-up observations of these candidate stars using more powerful instruments, such as the James Webb Space Telescope, to obtain more precise data and search for other signs of intelligent extraterrestrial life in these systems. So while these findings do not guarantee the presence of extraterrestrial civilizations, they open up exciting new avenues in the search for life beyond our solar system. Details of the study are published in the journal Monthly Notices of the Royal Astronomical Society.