Dyson Spheres Around Black Holes Could Reveal Alien Civilizations, Scientists Say [View all]

[Judi Lynn]

Artist's impression of a Dyson structure. (cokada/iStock/Getty Images Plus)

SPACE

MICHELLE STARR17 AUGUST 2021

One of the biggest questions we have about the Universe is: Are we alone as a technologically advanced species? This raises other questions: If aliens are out there, what would their technology look like? And, pertinently, how could we detect it?


A new study has laid out some answers to these questions – at least, if the technology in question is a type of insane energy harvester called a Dyson sphere, drawing down energy from a black hole.

"In this study, we consider an energy source of a well-developed Type II or a Type III civilization. They need a more powerful energy source than their own Sun," the researchers write in their paper.

"An accretion disk, a corona, and relativistic jets could be potential power stations for a Type II civilization. Our results suggest that for a stellar-mass black hole, even at a low Eddington ratio, the accretion disk could provide hundreds of times more luminosity than a main sequence star."

The concept of a Dyson sphere was popularized by theoretical physicist Freeman Dyson in the 1960s as a solution to the problem of power consumption that exceeds the capabilities of a civilization's planet. The sphere itself is built around the planetary system's star – a megastructure that harvests the star's energy at the source.

Dyson's paper proposed that infrared emissions of thermal energy might escape as the Dyson structure captures and converts stellar energy, which could hypothetically give away the presence of these hypothetical structures. This infrared signature, if we could detect it, would allow us to home in on alien civilizations.

More:
https://www.sciencealert.com/wild-new-paper-tells-us-how-we-might-be-able-to-spot-aliens-black-hole-dyson-spheres