Scientists have long theorized that Dyson spheres, massive structures that could hypothetically be built by advanced civilizations to harness the energy of their star, might offer a way to detect alien life. Recent studies have hinted at potential evidence of such megastructures, sparking intrigue in the scientific community.
Researchers believe that a civilization constructing a Dyson sphere could produce detectable signs, such as unusual light patterns or infrared radiation. These would be distinct from natural celestial phenomena, offering clues that something artificial might exist. New observations have revealed unusual star dimming and energy signatures that some scientists speculate could be the work of advanced extraterrestrial technology.
While this remains far from conclusive proof, it opens up exciting possibilities for the future of SETI (Search for Extraterrestrial Intelligence) research and the continued search for life beyond Earth. The pursuit of Dyson sphere evidence showcases humanity’s growing interest in not just finding life, but understanding the potential technological advances of civilizations light-years away.
What could be the ultimate solution to the energy needs of an advanced civilization? Renowned British-American physicist Freeman Dyson theorized it might be a massive shell of mirrors or solar panels that fully encircles a star, capturing all its energy.
“In a few thousand years of industrial development, any intelligent species should be found occupying an artificial biosphere surrounding its parent star,” Dyson wrote in a 1960 paper where he first outlined this concept.
Although it sounds like science fiction—and it is—Dyson credited Olaf Stapledon’s 1937 novel Star Maker for the idea. The late physicist was a professor emeritus at the Institute for Advanced Study in Princeton, New Jersey.
Despite its science fiction roots, the concept gained traction, particularly coming from a thinker like Freeman Dyson, whom some believe deserved a Nobel Prize early in his career. The hypothetical megastructures became known as Dyson spheres, though Dyson later clarified they would be a “loose collection or swarm of objects orbiting the star.”
In his paper, Dyson noted that such structures would emit waste heat detectable as infrared radiation, suggesting this is a potential method for searching for extraterrestrial life. However, he cautioned that infrared radiation alone wouldn’t confirm alien intelligence and that searching for such sources could also reveal new types of natural astronomical objects.
“Scientists at the time were receptive—not to the idea that alien civilizations would necessarily be found, but that waste heat was a promising avenue to explore,” said George Dyson, technology writer and author, and the second of Dyson’s six children. “Science fiction, from *Footfall* to *Star Trek*, embraced the idea, while social critics used the Dyson sphere to question the wisdom of unchecked technological growth.”
In the 1960s, searching for Dyson spheres was impossible. However, in recent years, researchers, including those at the SETI Institute and Fermilab, have begun the search. A new study examining 5 million stars in the Milky Way has identified seven potential candidates that might host Dyson spheres, drawing both attention and alternative theories.
Possibilities
The authors of the study, published on May 6 in the *Monthly Notices of the Royal Astronomical Society*, specifically aimed to search for Dyson spheres by looking for unexplained infrared heat near stars.
Using historical data from infrared-detecting telescopes, the research team focused on stars located within 1,000 light-years of Earth. “We started with a sample of 5 million stars and applied filters to minimize data contamination,” explained lead author Matías Suazo, a doctoral student at Uppsala University in Sweden.
“So far, we have seven sources emitting infrared light that we can’t yet explain, which makes them stand out,” Suazo said. However, he cautioned that there is no conclusive evidence that these stars have Dyson spheres.
Possible natural explanations include a coincidental alignment with a galaxy in the background, planetary collisions creating debris, or the stars being young and surrounded by hot debris disks from which planets may eventually form.
The researchers drew their data from two active space telescopes—NASA’s Wide-field Infrared Survey Explorer (WISE) and the European Space Agency’s Gaia—as well as from The Two Micron All Sky Survey (2MASS), a collaboration between the University of Massachusetts and NASA’s Jet Propulsion Laboratory, which conducted an infrared survey of the sky between 1997 and 2001.
The candidate stars identified are all red dwarfs, the most common type in our galaxy. Being smaller and dimmer than the Sun, red dwarfs are harder to study in follow-up observations. It’s still unknown if these stars have planets, as no telescope has yet detected any orbiting them. However, since many of the thousands of exoplanets identified so far orbit red dwarfs, their presence is likely. NASA notes that planets around red dwarfs have a higher potential for being habitable.
An earlier study from March, using the same data sources, also discovered infrared anomalies in a sample of 5 million stars within our galaxy.
A job for the Webb space telescope
She plans to compare her candidates against Suazo’s model to identify any potential connections.
“You need to rule out all other possibilities before considering Dyson spheres,” she added. “This includes eliminating explanations like debris disks or planetary collisions, which advances science in other areas of astronomy—so it’s a win-win.”
Both Contardo and Suazo agree that further research is necessary. They hope to eventually use NASA’s James Webb Space Telescope to observe the candidate stars directly, although securing time with the telescope can be a lengthy process. Suazo speculates that if Dyson spheres exist, they could unlock unimaginable possibilities: “With the energy of an entire star, we could achieve interstellar travel or even move our solar system to a preferred location.”
However, the technology and raw materials needed to build such structures are far beyond humanity’s capabilities. “They are so massive that dismantling an entire planet like Jupiter might be required,” Suazo noted, referencing Dyson’s suggestion.
This supercolossal scale suggests Dyson spheres if they exist, are extremely rare. “The significance of this work is that it provides strong evidence that Dyson spheres are not common in our galaxy,” said study co-author Jason Wright, a professor of astronomy and astrophysics at Penn State University. “Whatever Matías Suazo has found—likely stars surrounded by material from rare events, like planetary collisions, or possibly Dyson spheres—they are rare and deserve further study, perhaps by the James Webb Space Telescope.”
Broken spheres
Dyson passed away in 2020 before any of his spheres were discovered—just one of many ideas linked to his name. “As a young scientist, Dyson demonstrated that three competing quantum theories were the same, effectively ending the debate,” said William Press, a professor at the University of Texas at Austin, who was not involved in the study. By the time of his death, he was recognized as a provocative and creative thinker.”
George Dyson, his son, highlighted his father’s interdisciplinary brilliance: “With a short attention span and a disdain for bureaucracy, he contributed to five fields of mathematics, eleven areas of physics, as well as theoretical biology, engineering, literature, and public affairs. Many of his ideas were controversial, driven by his belief that ‘It is better to be wrong than to be vague.'”
Tomotsugu Goto, an associate professor of astronomy at Taiwan’s National Tsing Hua University, suggested that the approach of the new study could advance the search for extraterrestrial intelligence.
A May 23 paper responding to Suazo’s study suggested that at least three of the seven stars might be misidentified Dyson spheres and could be “hot DOGs” (hot dust-obscured galaxies). The remaining four stars might also be explained in this way.
Because the search for Dyson spheres intersects with fundamental questions about humanity’s place in the universe, the study spans basic sciences, philosophy, and religion, potentially sparking more interest from young scientists, according to Zaza Osmanov, a SETI affiliate and associate dean at the Free University of Tbilisi in Georgia. However, Osmanov noted that natural phenomena might still explain the seven candidates. “Future research is essential.”
As for Dyson, George believed his father would remain skeptical that these observations indicate a technological signature.
