Is there anyone else out there? For decades, our search for intelligent life has focused on looking for radio signals or atmospheres with remote biological signs. Even a simple amoeba on a distant planet would make us very excited.
However, there is a new technique for searching for signs of life in the universe: “techno-signatures,” which are evidence of technology on a cosmic scale. If all this sounds like Greek to you, stick with us and keep reading.
The Mystery of Excess Heat
The world of astronomy has just found something that lies on the border between science and science fiction. We are sure that Jules Verne would have loved this discovery. A group of astronomers has used a combination of data from NASA and ESA to make a somewhat cautious discovery. By comparing data, they have found seven red dwarf stars that are emitting a completely anomalous heat pattern. Yes, we could make jokes about Snow White’s seven dwarfs, but this is a serious article.
Looking at the issue, these particular stars are releasing an amount of average infrared radiation that cannot be explained by conventional astrophysical models. However, they fit perfectly with what we would need from a Dyson sphere. We are not referring to the Dyson vacuum cleaner that is so efficient at sucking up all the dust and pet hair in our homes. Although it is not yet conclusive proof that alien life exists, it is a list of exceptional candidates that challenge our current explanations of what the universe is. The study was published in the journal Monthly Notices of the Royal Astronomical Society (MNRAS).
Megaconstruction according to Freeman Dyson
Returning to the subject of this anomalous heat, we must go back in time to 1960. In that year, physicist Freeman Dyson proposed a brilliant hypothesis: any advanced civilization would, over time, exhaust the energy resources of its home planet (rings a bell, right?). The only solution for this advanced civilization to continue prospering would be to capture the total energy of its star. To achieve this, they would need to build a Dyson sphere, or a Dyson Swarm.
This Dyson Swarm would be a vast collection of solar panels and satellites that would encapsulate the star. These structures would absorb the high-energy visible light radiated by the star. However, according to physics, this energy could not be used without generating waste heat. To prevent overheating, this Dyson Swarm would dissipate that heat into space, leaving a “waste heat signature” that astronomers would look for.
You can imagine the surprise of astronomers when they came across seven red stars that have all the characteristics that Freeman Dyson described 65 years ago.
But why red dwarf stars?
To begin with, the team of scientists was not looking for stars like our own. They are focusing on these red dwarf stars, which are the silent giants of the universe. It is believed that 75% of all stars in the Milky Way are red dwarf stars. They are much smaller than our sun.
No, that lack of brightness is necessary for the search for techno-signatures. Because they are so small, the residual heat from a mega-structure would not be so easily camouflaged by starlight. Being a much weaker star, finding excess artificial heat around it is much easier, which is why scientists consider these dwarf stars to be the perfect target for searching for Dyson spheres… and for now, it seems they have found them.
For now, we will have to wait until the James Webb Telescope has some free time to point its infrared lens to these dwarf stars and study them thoroughly. In the meantime, we will keep speculating about alien life outside our planet!