Controversial startup’s plan to ‘sell sunlight’ using giant mirrors in space would be ‘catastrophic’ and ‘horrifying,’ astronomers warn
A Californian start-up’s controversial plan to put 4,000 tennis court-sized mirrors into orbit around the Earth is “catastrophic” and “horrible”, astronomers warn.
Reflect Orbital, founded in 2021, recently took the first step in a project to sell sunlight at night by bouncing the sun’s rays off giant “reflectors” that can redirect the vital resource almost anywhere on our planet. In doing so, the company aims to extend daylight hours in specific locations, allowing paying customers to generate solar power, grow crops and replace street lighting.
As a first step, Reflect Orbital recently submitted an application to the US Federal Communications Commission (FCC) to launch its first test satellite, EARENDIL-1, in early 2026. If this request is granted and the first tests are successful, the startup plans to launch up to 4,000 similar satellites by 2030, company representatives recently told Live Science’s sister site. Espace.com.
Once in low Earth orbit (LEO), EARENDIL-1 would deploy a square reflector measuring up to 59 feet (18 meters) in diameter, giving it an area of approximately 3,500 square feet (325 square meters). This would allow the mirror to illuminate a single part of the Earth’s surface up to 5 kilometers across at a time. From the ground, the light in one of these areas would be up to four times brighter than that in the atmosphere. full mooncompany representatives said.
However, future reflectors in the planned constellation could have mirrors up to 177 feet (54 m) in diameter, which would likely create larger and more intense points of light.
Reflect Orbital said it could minimize the effects of its light pollution by moving the mirrors away from Earth when not in use. “Our service is highly localized,” company representatives told Space.com. “Each reflection covers a defined area for a finite period of time rather than providing continuous or widespread illumination.”
However, these assurances have not really reassured scientists.
“A terrible idea”
The reflectors would orbit the Earth in a sun-synchronous orbit, which would cause them to circle the Earth from pole to pole, perpendicular to the planet’s rotation. They would be positioned to constantly align with the day-night divide on our planet, essentially allowing the mirrors to reflect the sun’s rays from the day side to dark places. In theory, this would light up areas just after sunset or before dawn.
But even though the basic physics behind the idea is sound, experts say it’s much easier said than done — and they’re skeptical the company can pull it off.
Their plan “is flawed from the start, technically speaking”, Fionagh Thomsona researcher at Durham University in England who specializes in space ethics, told Live Science in an email. “This is very unlikely to come to fruition due to the complexity of the engineering involved and attempting to operate in busy orbits such as LEO.”
In fact, this idea has been tried – and then abandoned – before. In 1993 and 1999, Russia attempted to launch two similar reflectors, dubbed the Znamya satellites, but canceled the program after having difficulty controlling the satellites, both of which quickly burned up in the atmosphere. (No other reflectors have been released since.)
Researchers writing The conversation And Think big are also wondering if the mirrors are capable of providing one of the company’s future flagship services: solar power generation.
In theory, the mirrors could be used to illuminate giant solar farms on the planet’s surface, extending the time they can produce electricity. However, the resulting light would be thousands of times dimmer than that of the midday sun, meaning the light panels would generate a tiny fraction of their normal energy. Additionally, a single mirror could focus light on the same spot for up to four minutes at a time, the researchers predict.
Even if the mirrors could collectively generate enough power, it would be “incredibly expensive” compared to other forms of renewable energy, Thomson said.
Overall, “this is a really bad idea.” Samantha Lawleran astronomer at the University of Regina in Canada, told Live Science in an email. However, there is still a good chance that the EARENDIL-1 mission will be approved by the FCC, she speculated.
Blinded by the light
A single mirror is unlikely to have a major impact on the night sky. But if Reflect Orbital’s proposed constellation comes to fruition, astronomers say it will be increasingly difficult to study stars beyond the glare of thousands of “new stars” streaking across the night sky.
Robert Masseydeputy executive director of the UK’s Royal Astronomical Society, told Space.com that the astronomy community was “seriously concerned about the development, its impact and the precedent it sets.”
While other spacecraft, such as SpaceX’s Starlink satellites, accidentally reflect light back to Earth’s surface, astronomers are particularly concerned about the deliberate generation of light pollution proposed by Reflect Orbital.
“The main goal of this project is to light up the sky and extend daylight, and obviously, from an astronomical point of view, that’s pretty catastrophic,” Massey said.
For unlucky astronomers who find themselves in one of the mirrors’ bright spots, it would also be nearly impossible to see other stars in the night sky, Lawler said. Previous research This concept also showed that looking directly at the reflectors through a telescope or binoculars could cause eye damage, she added.
Since a mirror can be suddenly rotated or repositioned anywhere on Earth without warning, there is no guaranteed way to avoid this. And a sudden flash from the movement of a reflector could also distract plane pilots during takeoff or landing, with potentially disastrous consequences, several experts said.
Previous research on light pollution has also shown that it can change the behavior of a wide range of animal and plant species, as well as disrupt the sleep cycles of humans.
“A small California business can, with a few million dollars and the approval of a single U.S. federal agency, change the night sky for everyone,” Lawler said. “It’s horrible.”
Additional problems
While astronomers are mainly concerned about light pollution and invisible radio pollution If these mirrors are likely to be created, the predicted swarm could prove dangerous in other ways.
For example, the large size of mirrors makes them more likely to be hit by micrometeorites or rapidly multiplying fragments of planets. space debris that surround our planet, Lawler said. This could leave the reflectors “riddled with holes”, making them harder to control, she added.
If operators lost control of a mirror, it could end up rotating, like NASA’s Advanced Composite Solar Sail System, which started to tumble from one end to the other after being deployed in August 2024. If this happened, the mirrors would flash uncontrollably in the night sky.
Additionally, the number of satellites planned across the world is already higher than the number of spacecraft considered by experts. predict can operate safely in LEO. And the new reflectors would eventually fall back to Earth at the end of their operational life, which could lead to problems such as air pollution by metals.
As for the project’s potential impacts on wildlife, Reflect Orbital has committed to carrying out an environmental risk assessment, but only after the launch of EARENDIL-1, according to Space.com.
