A survey offive million distant solar systems, aided by 'neural network' algorithms, has discovered 60 stars that appear to be surrounded by giantalien 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.
A survey of five million distant solar systems, aided by 'neural networks,' has discovered 60 stars that appear to be surrounded by gigantic alien power plants. Such solar power-collecting 'Dyson spheres,' physicists argue, would reveal themselves by radiating more heat than usual
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.
Two teams of astronomers, led by Matías Suazo at Uppsala University in Sweden and Gaby Contardo at the International School for Advanced Studies in Italy, ran the latest hunt for the tell-tale infrared data that might reveal a distant 'Dyson sphere.'
The researchers merged data from theEuropean Space Agency's Gaia satellite, theWide-field Infrared Survey Explorer (WISE)space telescope and the ground-based infrared telescope survey MASS2.
While there may be other explanations for the excess infrared signatures they found, Suazo noted, 'The most fascinating explanation could be actual Dyson spheres.'
On their hunt for 'Dyson spheres,' the researchers merged data from the European Space Agency's Gaia satellite, the Wide-field Infrared Survey Explorer space telescope and the ground-based infrared telescope survey MASS2. Above, stars that could have ET power plants
Suazo's groupin 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,toldNew 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 alarge 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 theMonthly Notices of the Royal Astronomical Society.
If the stars prove to be surround by alien power plants, the researchers said, they'd likely be a variant on the all-encompassing Dyson sphere dubbed a 'Dyson swarm' (illustrated above)
A Dyson swarm could come in the form of a large fleet of satellites orbiting these stars as a means of collecting energy - and would only partially cover the star (as illustrated above), as opposed to the big shell of the classic, original Dyson sphere concept
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.
'A few of those objects appear to be young stars,'Contardo's group acknowledged in their study; the young stars would be likely to project infrared as they heated clouds of debris and not-yet-fully-formed planets in their equally young solar system.
WhileContardo said that both her group's and group's candidate stars were 'interesting,' she admitted that astronomers and other scientists will 'need follow-up observations to confirm anything.'
Suazo's group suggested that optical spectroscopy would be one helpful next step, a technique that has separated interesting older stars from those younger stars surrounded by debris and 'proto-planets' in the past.
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, claimsDan Hooper, a physicist at the Fermi National Accelerator Laboratory.
