Reflect Orbital stages ground light demo of its space-mirror plan

Locals in a rural stretch of California near the town of Lone Pine, in the Sierra Nevada, were startled earlier this month by dazzlingly bright light shining down from nearby mountains at night and illuminating a swathe of desert below. It was a demonstration by Reflect Orbital, a US startup that aims to launch 50,000 satellites in the next decade to illuminate parts of the world at night with reflected sunlight.

The demonstration did not use a satellite or a mirror. Large mobile lights were erected near Mount Whitney, and Reflect Orbital compared the radiance to that of a full moon. The company said it was a realistic simulation of one benefit of the technology: helping search-and-rescue teams and other emergency responders at night. It partnered with a local search-and-rescue team for the test. A spokesperson said such teams are expected to be the first customers and that the test was run alongside people who would use the technology. One local resident called the lights "blinding".

The real hardware is still to come. In July, the Federal Communications Commission (FCC) approved Reflect Orbital's proposal to launch an initial demonstration satellite next year. It would orbit the Earth and use a 59ft-diameter mirror to reflect sunlight in 3-mile-wide beams, with strengths ranging from moonlight up to the brightness of the sun at noon. The mirrored satellites would ascend to about 400 miles (645km) before reflecting light back. Other planned uses besides emergency response include bathing crops in sunlight, replacing broken streetlights and providing solar power for military operations, all summoned by the tap of a button on an app.

Critics are far less enthusiastic. A coalition of environmentalists and astronomers has criticized the company and the FCC for threatening a harmful change to the separation of night and day, affecting sleep, wildlife and the ability to see the stars. Jan Hasselman, a senior attorney with Earthjustice, called it "an idiotic project" and said there are "a huge number of unresolved questions and significant potential impacts". He argued that all life on Earth evolved around the rhythm of day and night, and that there needs to be discussion and analysis before anyone is granted the right to fundamentally alter the night sky. In August, four groups represented by Earthjustice asked the FCC to reconsider its approval.

The objections run wider. Animals such as birds, insects and mammals rely on a reliable change between day and night to feed, shelter and mate, and any change could be disastrous for some species. Astronomers have complained that the glare would worsen existing light pollution and spur a rush to put more satellites in orbit (the article notes SpaceX plans to place 1 million celestial datacenters around Earth), obscuring stars and creating more space debris that could come back down as pollution. There are also concerns that scrambling night and day would harm health by disrupting circadian rhythms, and that looking directly at the glare would harm eyes, much as during a solar eclipse.

Reflect Orbital says its technology will aid the environment by boosting solar panel output at night, which would reduce reliance on fossil fuels. Some climate scientists warn against meddling with the amount of the sun's energy reaching Earth. David Ho, a climate scientist at the University of Hawaii, said global warming comes from a radiative imbalance caused by greenhouse gases, and noted that some people promote space mirrors facing away from Earth to cut warming: "Imagine wanting to turn those mirrors around so that the Earth gets hotter."

The company says it has had "substantive discussions" with scientists and astronomers so that astronomical sites, national parks and other wildlife-rich areas are avoided. A spokesperson said: "We welcome oversight and want to play a role in shaping it."

Key facts

Reflect Orbital aims to launch 50,000 satellites in the next decade to reflect sunlight onto parts of the Earth at night.
The California demonstration near Lone Pine used large mobile lights on the ground near Mount Whitney, not a satellite; the company compared the radiance to a full moon.
The FCC approved an initial demonstration satellite in July, planned for launch next year, with a 59ft-diameter mirror casting 3-mile-wide beams.
In August, four groups represented by Earthjustice asked the FCC to reconsider its approval.
Critics cite harm to wildlife, sleep, eyesight and stargazing, plus more satellites and space debris; the company points to search-and-rescue use and cleaner solar power.

Why it matters

This would be the first step toward lighting parts of the Earth at night from orbit, a plan the article describes as almost sci-fi in ambition. The FCC has already approved an initial demonstration satellite, so the argument is no longer hypothetical. Critics say it would alter the separation of night and day that, in Hasselman's words, all life on Earth evolved around, and the dispute now centres on whether the FCC approval should stand.

Who it affects

Local residents near the test site were startled by the lights, and one called them "blinding". Wildlife such as birds, insects and mammals that depend on the day and night cycle could be affected, according to the critics. People's sleep and circadian rhythms are a health concern, and astronomers worry about the view of the stars. On the other side, search-and-rescue teams, farmers, operators of solar panels and the military are named as intended users.

How to use it

Nothing is available to use yet. Reflect Orbital says its first customers are expected to be search-and-rescue teams. Other planned uses are lighting crops, replacing broken streetlights and providing solar power for military operations, all requested by the tap of a button on an app. The initial demonstration satellite is due to launch next year.

How solid is it

The account comes from a Guardian report that includes statements from the company, an Earthjustice attorney and a University of Hawaii climate scientist. The FCC approval and the August request for reconsideration are stated as facts. The company's claims about benefits, such as helping rescuers and cutting fossil fuel use through boosted solar output, are its own and are not independently tested in the article. The source reports no scientific measurements of the demonstration's effect on wildlife or sky brightness.

Risks and caveats

The California event was a simulation with ground lights, so it says little about how a space mirror would behave. The article reports no FCC response to the reconsideration request, and no launch provider or exact launch date. The FCC approval covers only an initial demonstration satellite, not the 50,000. Critics' concerns about wildlife, health, eye damage, light pollution and debris are warnings, not measured outcomes. Reflect Orbital says it has held "substantive discussions" with scientists and astronomers to keep sites such as astronomical sites and national parks out of the light.

“The proposal for 50,000 of these satellite mirrors is crazy and would really end the night sky as we know it.”

— Jan Hasselman, senior attorney, Earthjustice