Reflect Orbital, a California-based startup, plans to launch thousands of mirrors into space to deliver sunlight on demand. The startup believes that one day, solar power could be used even during non-peak times and could be used to illuminate disaster zones.

“‘Trying to build something that could replace fossil fuels and really power everything,’” Reflect Orbital CEO Ben Nowack said, according to The New York Times. The mirrors, part of a massive orbital constellation, will gather sunlight that normally misses Earth and channel it to specific places.

The US Federal Communications Commission (FCC) is reviewing the proposal, which includes a prototype satellite with a 60-foot mirror. Reflect Orbital plans to launch 50000 mirrors by 2035, which will create a satellite constellation more than five times larger than the current biggest satellite network.

Scientists warn the mirrors could cause serious light pollution. Silverado Hills Observatory astronomer John Barentine said the reflected beams would be “four times brighter than the full moon” and could affect wildlife and ecosystems. The New York Times also noted risks to circadian rhythms, plant cycles, and astronomical observations.

Reflect Orbital claims that these mirrors’ beams can be turned off quickly and sent away from specific areas. Nevertheless, experts have questioned these claims, stating that light will always scatter in the atmosphere and that thousands of satellites could become visible to the naked eye, outshining stars.

The FCC’s role is limited to radio frequency interference and disposing of satellites but not to their environmental impacts. “Space mirrors would utterly destroy [the night sky] and permanently scar the natural landscape,” Royal Astronomical Society Deputy Executive Director Robert Massey said.