A survey of five million distant solar systems, aided by ‘neural network’ algorithms, has discovered 60 stars that appear to be surrounded by giant alien power plants.
Seven of the stars — so-called M-dwarf stars that range between 60 percent and 8 percent the size of our sun were recorded giving off unexpectedly high infrared ‘heat signatures,’ according to the astronomers.
Natural, and better understood, outer space ‘phenomena,’ as they report in their new study, ‘cannot easily account for the observed infrared excess emission.’
Ever since theoretical physicist Freeman Dyson first proposed the idea at Princeton in 1960, astrophysicists have speculated that advanced extraterrestrials might have constructed massive solar energy collectors around one star or more.
While powering their spacefaring ET civilizations, these hypothetical ‘Dyson spheres,’ would reveal themselves by radiating more heat than usual, the physicist argued.
Astrophysicists and planetary scientists call ‘Dyson spheres’ and other concepts like them ‘technosignatures,’ or simply signs of technology out there in the universe.
Technosignatures can range from these incredible feats of engineering to more humbling signs, like technologically made pollution including nitrogen dioxide gas from combustion exhaust or the chlorofluorocarbons (CFCs) that once threatened Earth’s ozone layer years ago, both detectable via telescopes light-years away.
Suazo’s group in Sweden determined that seven, red M-dwarf stars, each no farther than 900 light-years from Earth, appeared to be producing as much as 60 times more infrared heat than would be expected based on their size.
For each red dwarf star, they calculated how much of its radiation would have to be blocked off by some possible energy-collecting tech in order to produce the measured ratio of infrared heat vs. visible light.
The values ranged from 3 percent to 16 percent coverage for the seven unusual stars they identified.
‘This isn’t like a single solid shell around the star,’ as one member of Suazo’s team, astrophysicist Jason Wright at Pennsylvania State University, told New Scientist.
If these stars proved to be surround by alien power plants, in other words, they’d likely be a variant on the all-encompassing Dyson sphere dubbed a ‘Dyson swarm.’
Such a swarm could come in the form of a large fleet of satellites, which would orbit these stars as a means of collecting energy.
‘Additional analyses are definitely necessary to unveil the true nature of these sources,’ the team wrote in their study, published this month in the Monthly Notices of the Royal Astronomical Society.
The findings from Contardo’s group in Italy were more broad and utilized a different machine-learning computer model to hunt for infrared ‘technosignatures’ of Dyson spheres, partial spheres or swarms.
They identified 53 candidates, including odd infrared heat around a few larger sun-like stars, at a range that extended farther than Suazo’s team’s candidate stars: as far as 6,500 light years from Earth.
WHAT ARE ‘DYSON SPHERES’?
A proposed method for harnessing the power of an entire star is known as a Dyson sphere.
First proposed by theoretical physicist Freeman Dyson in 1960, this would be a swarm of satellites that surrounds a star.
They could be an enclosed shell, or spacecraft spread out to gather its energy – known as a Dyson swarm.
If such structures do exist, they would emit huge amounts of noticeable infrared radiation back on Earth.
But as of yet, such a structure has not been detected.
Although it is difficult to know how an advanced civilisation might look, one thing it would almost definitely require is large quantities of energy.
Dark energy, which makes up 68 per cent of the universe, is causing our universe to expand at an accelerating rate.
For an advanced civilisation to survive in 100 billion years time when the universe is dominated by dark energy, it will need to harvest stars to fuel its vast energy needs.
One way it could do this is by building giant spheres or Dyson Spheres around stars to collect their light and power their existence, claims Dan Hooper, a physicist at the Fermi National Accelerator Laboratory.
