Reflect Orbital Wins U.S. Approval for Test Satellite Using Radio Spectrum

According to Lianhe Zaobao citing ABC, U.S. startup Reflect Orbital plans to send large mirrors into space to reflect sunlight back to the ground after sunset and charge solar farms, cities or event organizers for the service. The U.S. Federal Communications Commission recently approved the company’s first test satellite to use radio spectrum, bringing the “selling sunlight” concept closer to reality.

Under the company’s plan, the mirrors would be made of ultra-thin aluminized film and operate in low Earth orbit at about 625 kilometers above the ground. Reflect Orbital says the first test satellite is expected to create only a weak, moving light spot about 5 kilometers wide, while its long-term goal is to deploy as many as 50,000 satellites to provide stronger illumination for up to about one hour around sunset and sunrise. The satellites would mainly operate at dusk and before dawn and could not provide continuous lighting through most of the night.

The company says solar farms could buy reflected sunlight after dark as a partial substitute for large battery storage, and that the system could also extend crop exposure to light, illuminate city streets and assist search-and-rescue operations after disasters. But experts have questioned the business model. Salazar, a former founding engineer at Reflect Orbital, said a single satellite would not reflect enough light to significantly boost solar generation and might be better suited to outdoor events such as parties, where it could provide lighting roughly comparable to moonlight. Monash University astronomer Brown estimated that about 3,000 satellites and mirrors 54 meters wide per satellite would be needed to reach about 20% of midday sunlight, and said each satellite could illuminate the same location for no more than three and a half minutes. He added that giving one location an hour of near-daylight illumination could require tens of thousands of satellites and cost an estimated USD 10 million to USD 20 million, far above current battery storage costs.

Scientists have also warned that large-scale nighttime illumination from space could disrupt human and wildlife circadian rhythms. The head of an international scientific organization representing more than 30 countries and thousands of researchers has written to U.S. regulators, warning that space mirrors could disorient migratory birds, trigger early coral spawning, disturb nocturnal animals, interfere with astronomical observations and briefly dazzle pilots.