Black holes surrounded by massive energy harvesting structures could fuel alien civilizations

An artist’s depiction of a distant quasar. (Credit: WM Keck Observatory)

Black holes are among the most energetic objects in the Universe. But its immense mass generates a gravitational field so intense that not even light can escape from it. So is it possible that such an advanced alien civilization could use a black hole as a massive source of energy? Scientists say yes.

Black holes are among the most energetic objects in the Universe. But its immense mass generates a gravitational field so intense that not even light can escape from it. So is it possible that such an advanced alien civilization could use a black hole as a massive source of energy? Scientists say yes.

This hypothetical structure became known as the Dyson Sphere, and finding it one day would be unmistakable proof of the existence of super advanced alien civilizations.

The problem is that to this day, we have never come across one of these. It’s all in the realm of ideas, and in the realm of ideas, scientists have been allowed to speculate whether the Dyson spheres around black holes could power alien civilizations. And according to an article just published in the Monthly Notices of the Royal Astronomical Society, that would not only be possible, it would be a phenomenal energy source.

This is because extremely energetic processes take place in the surroundings of a black hole. According to the study, its accretion disk, corona, and relativistic jets would make an excellent power plant. The accretion disk of a relatively small black hole alone could provide 10 times more energy than a star like the Sun.

The accretion disk is made up of a plasma of superheated matter that rotates, at speeds close to the speed of light, around the event horizon, which is the black hole’s point of no return. But the accretion disk is not your best source of energy. If our hypothetical aliens were able to harvest the energy from the relativistic jets, they would surely avoid any risk of blackout for a long time.

Relativistic jets are extremely energetic plasma jets that emerge from the poles of a black hole and are launched into space at speeds close to the speed of light. If they could capture all the energy from relativistic jets, including kinetic ones, they could generate up to 5 times more energy in total. In other words, a complete Dyson Sphere around a black hole could provide 50 times more than all the energy generated by our Sun.

The study concludes that something like this is physically possible, although it seems very far from reality. But imagination exercises like this are important in determining, not what actually exists, but what could possibly exist. Thus, we could more easily identify evidence of an alien civilization, if we ever find it.

Megastructures like the Dyson Sphere are probably unviable. Even for the most advanced civilizations, if they exist. The amount of matter and energy necessary for its construction would make this solution practically impossible.

A more realistic idea would be, instead of a complete sphere, a swarm of Dyson. A large number of satellites orbit the black hole and collect some of its energy. Now, how these satellites would withstand the intense heat and how they would transmit the collected energy to the planet, then, is the problem of the extraterrestrials.