Astronomers Warn Reflect Orbital's Plan to 'Sell Sunlight' From Space Mirrors Could Be 'Catastrophic'

A California startup called Reflect Orbital has asked the U.S. Federal Communications Commission for permission to launch a single test satellite, EARENDIL-1, in early 2026. If the application is granted and the tests work, company representatives have told Space.com, Live Science's sister site, they envision as many as 4,000 similar satellites in orbit by 2030. Astronomers are calling the idea catastrophic and horrifying.

Founded in 2021, Reflect Orbital wants to sell sunlight after dark. Giant mirrors in low Earth orbit would bounce solar rays onto chosen spots on the night side of the planet. Paying customers could then generate solar power, grow crops or replace urban lighting during hours that would otherwise be dark.

The test satellite would unfurl a square reflector up to 59 feet (18 meters) across, with a surface area of about 3,500 square feet (325 square meters). It could light a patch of ground up to 3 miles (5 kilometers) wide, and the company says the light inside that patch would be as much as four times brighter than the full moon. Later satellites in the constellation could carry mirrors up to 177 feet (54 meters) across, which would likely make larger and more intense bright spots.

The mirrors would fly in a sun-synchronous orbit, circling pole to pole and staying aligned over the day-night divide. From there they could throw light from the daylit side onto ground just after sunset or before dawn. Experts say the basic physics is sound. Fionagh Thomson, a Durham University researcher who specializes in space ethics, calls the plan flawed from the outset and says the engineering complexity and crowded orbits make it unlikely to succeed. Russia tried something similar with its Znamya satellites in 1993 and 1999, then canceled the program after struggling to control them; both burned up in the atmosphere. No reflectors have been launched since.

The solar power pitch also draws skepticism. Researchers writing in The Conversation and Big Think point out that reflected light would be thousands of times weaker than the midday sun, so illuminated panels would produce only a sliver of their normal output. They predict a single mirror could hold light on one spot for no more than four minutes. Even if the numbers worked, Thomson says, the power would be "eye-wateringly expensive" next to other renewables. Samantha Lawler, an astronomer at the University of Regina, calls it a terrible idea, though she thinks the FCC may well approve EARENDIL-1.

The main worry for astronomers is light. One mirror would barely affect the night sky, but thousands would make it much harder to study the stars. Robert Massey of the U.K.'s Royal Astronomical Society says the community is seriously concerned about the impact and the precedent. Satellites such as SpaceX's Starlink reflect light accidentally. Massey notes that lighting the sky is this project's central goal, which he calls pretty catastrophic from an astronomical perspective.

Lawler says anyone caught in a bright spot would struggle to see any other stars. Past research, she adds, shows that looking at the reflectors through a telescope or binoculars could damage eyes. A mirror could be repositioned anywhere without warning, so there is no guaranteed way to avoid this. Several experts say sudden flashes could distract pilots during takeoff or landing. Earlier research on light pollution has linked it to changed behavior in many animal and plant species and to disrupted human sleep.

Other hazards come with the size. Large mirrors are more exposed to micrometeorites and to the growing cloud of space junk, and Lawler says they could end up riddled with holes and harder to control. A mirror that slipped out of control could tumble and flash across the sky, as NASA's Advanced Composite Solar Sail System did after deploying in August 2024. Planned satellite numbers worldwide already exceed what experts think low Earth orbit can safely hold, and spent reflectors would fall back to Earth, raising the prospect of atmospheric metal pollution. Reflect Orbital says it will carry out an environmental risk assessment, but only after EARENDIL-1 launches.

The company says its service is highly localized, with each reflection covering a defined area for a finite time, and that it can turn mirrors away from Earth when idle. Lawler's objection is about who decides: a small company with a few million dollars and one federal agency's approval, she says, could change the night sky for everyone. The FCC's decision on EARENDIL-1 is the thing to watch.