For over half a century, the concept of megastructures orbiting distant stars has captivated the human imagination. Whether it’s a Dyson sphere harvesting the total energy output of a sun, or a colossal Ringworld spinning around a star, science fiction writers and futurists alike have dreamed of civilizations so advanced they could reshape entire solar systems. Yet despite their appeal, such grand cosmic constructions are often dismissed as flights of fancy—doomed by the harsh realities of gravity, orbital mechanics, and structural instability.
But what if we’ve been thinking about them all wrong?
A groundbreaking study from a scientist in Scotland has breathed new life into these futuristic visions. Professor Colin McInnes, an engineering scientist and holder of the James Watt Chair at the University of Glasgow, has demonstrated that under the right circumstances, megastructures like Dyson spheres and Ringworlds could exist—stable and intact—within binary star systems. His findings, published in the Monthly Notices of the Royal Astronomical Society, reveal tantalizing possibilities for cosmic engineering, with significant implications for the ongoing search for extraterrestrial intelligence (SETI).
The Sci-Fi Origins of Megastructures
Before we dive into McInnes’ work, let’s revisit the imaginative origins of these concepts.
The idea of the Dyson sphere was first introduced in 1960 by physicist Freeman Dyson. Dyson wasn’t thinking about aesthetics or utopias; he was contemplating raw efficiency. In a short paper published in Science, he speculated that a truly advanced civilization—what we might today call a Kardashev Type II civilization—would eventually need to capture the full energy output of its star to meet its growing needs.
Dyson proposed an enormous swarm or shell of objects encircling a star, collecting its energy and providing an immense habitat for life. He suggested that such megastructures could be detectable from Earth by their waste heat, emitting infrared radiation as they absorbed and re-radiated their star’s energy. Science fiction quickly embraced the idea. Star Trek fans will remember the Next Generation episode where the crew encounters an ancient Dyson sphere in deep space, dwarfing even the starships that had become a staple of sci-fi worlds.
Then there’s Larry Niven’s Ringworld, first published in 1970. Niven envisioned a colossal ring, a million miles wide, rotating around a star to provide artificial gravity through centrifugal force. The Ringworld concept took the Dyson sphere idea and made it more elegant—and more visually spectacular. But like Dyson’s theoretical shell, Niven’s Ringworld suffered from an inconvenient truth: physics makes it almost impossible to keep such structures stable without constant, active intervention.
Why Do Dyson Spheres and Ringworlds Fall Apart?
For decades, physicists have pointed out that a rigid Dyson sphere around a single star is inherently unstable. According to Newton’s Shell Theorem, an object inside a symmetrical spherical shell experiences no net gravitational force from the shell itself. That means the star at the center of a Dyson sphere could drift ever so slightly off-center. Once it does, the imbalance in gravitational pull would grow, creating forces that could twist and tear the shell apart. This instability would doom any solid Dyson sphere unless an advanced civilization found some way to constantly adjust and reinforce the structure.
The same problem applies to Ringworlds. Any slight nudge from a micrometeorite impact, stellar wind, or gravitational tug could knock the ring off its ideal orbit. Without active stabilization, the structure would begin spiraling toward its star, eventually leading to catastrophic collision and destruction.
Given these limitations, even optimistic scientists have argued that only partial Dyson swarms—constellations of satellites or habitats orbiting independently—would be plausible for energy-hungry alien civilizations.
McInnes’ Breakthrough: Stability in the Dance of Binary Stars
Enter Professor Colin McInnes. Inspired by his love for Larry Niven’s novels and a career spent studying orbital mechanics, McInnes decided to tackle the problem from a new angle. Instead of focusing on solitary stars, he considered binary systems—two stars locked in an orbital dance, circling each other under the influence of their mutual gravity.
Binary stars are extremely common in our galaxy. In fact, many, if not most, stars exist in such pairings. What if, McInnes wondered, the complex gravitational dynamics of two stars could provide a stable environment for massive orbiting structures?
In his recent work, McInnes applied the principles of the restricted three-body problem—a classical challenge in celestial mechanics that examines the motion of an object influenced by the gravity of two massive bodies. His approach was to model hypothetical rings and spheres in such systems to see if there were any stable equilibrium points where these megastructures could reside without tearing themselves apart.
The results were surprising.
Seven Equilibrium Points and the Promise of Stability
McInnes discovered that in a binary system with two stars of equal mass orbiting each other, a ring structure—essentially a Ringworld—could find stable positions in the orbital plane of the stars. Specifically, he identified seven equilibrium points where a ring’s center of mass could be located, allowing the structure to remain stable without needing constant adjustments.
These equilibrium points are similar in concept to Lagrange points in the two-body problem, such as the stable locations where satellites like the James Webb Space Telescope currently operate in our solar system. In McInnes’ model, some of these points allow the ring to enclose both stars, one star, or neither—offering several configurations for hypothetical alien engineers to exploit.
Even more intriguing, McInnes found similar results for hollow shells—Dyson sphere analogs—in binary systems. Though Newton’s Shell Theorem still applies, the presence of two gravitational centers creates unique conditions where shells might maintain stable positions, at least in theory.
His work suggests that a Dyson sphere enclosing one star in a binary system could, under the right conditions, achieve positional stability. This is particularly true if the two stars are of similar densities but different sizes. A shell around the smaller star could maintain a balanced orbit in relation to the larger companion.
Implications for SETI and the Hunt for Technosignatures
Why does this matter? If stable Dyson spheres or Ringworlds are physically possible in binary star systems, it expands the kinds of places astronomers can look for evidence of alien megastructures.
One of the major goals of SETI is to identify “technosignatures”—evidence of technology that indicates the presence of intelligent life. A Dyson sphere would be a prime example. It would absorb most of a star’s visible light and re-emit energy as infrared radiation. An advanced civilization harvesting the energy of an entire star would be hard to miss if we knew where to look.
McInnes’ research helps point us in the right direction. Instead of focusing exclusively on solitary stars like our sun, astronomers might do better to search binary systems—especially those where two stars orbit closely and might allow for stable megastructure configurations.
As McInnes puts it, “If we can understand when such structures can be stable, then this could potentially help direct future SETI surveys.” In other words, if we can predict where megastructures could exist, we increase our chances of finding them.
A telltale sign could be a bright star orbiting alongside an object that radiates an unusual amount of heat in the infrared spectrum. Even a nested set of Dyson spheres—concentric shells around each star of a binary pair—could be within the realm of possibility.
Engineering on an Astronomical Scale: Fantasy or Future?
Of course, we’re still a long way from building anything like a Dyson sphere. Humanity’s current engineering abilities are limited to relatively tiny projects like satellites, space stations, and (in the near future) perhaps moon or Mars habitats. Building a ring or shell around a star requires mind-boggling amounts of material, energy, and precision.
Dyson himself envisioned his sphere as the inevitable outcome of a civilization facing “Malthusian pressures”—the need to continually expand to support a growing population and energy demand. Some futurists argue that if a civilization can avoid self-destruction long enough, such massive projects become necessary rather than optional.
But whether it’s an inevitable technological endpoint or a flight of fancy, McInnes’ work provides a refreshing scientific perspective on these megastructures. His research shows that, at least in theory, the universe could support the existence of structures once thought impossible to maintain.
Conclusion: A New Frontier in the Search for Extraterrestrial Life
For scientists and science fiction fans alike, the dream of Dyson spheres and Ringworlds represents more than just spectacular cosmic architecture. It’s about what such structures imply: a universe filled with life advanced enough to harness the power of stars.
Thanks to Professor Colin McInnes, the idea of stable Dyson spheres in binary systems has shifted from implausible to possible. His insights may well shape the future of SETI and our understanding of how intelligent life might manifest on a cosmic scale.
In the vast expanse of space, with billions of stars—many in binary pairs—there may well be civilizations out there who’ve already solved the challenges of megastructure stability. And if they have, we might just catch a glimpse of their handiwork in the faint infrared glow of a distant star.
Until then, humanity will keep looking up—wondering, imagining, and searching for signs that we are not alone.
Reference: Colin R McInnes, Ringworlds and Dyson spheres can be stable, Monthly Notices of the Royal Astronomical Society (2025). DOI: 10.1093/mnras/staf028