Sleep experts warn FCC satellites could dramatically increase light pollution

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Sleep experts warn FCC satellites could dramatically increase light pollution

Public comment deadlines approaching for proposals that could brighten the night sky

EVANSTON, Ill. --- Northwestern University scientists and physicians are raising concerns about two proposals currently under review by the Federal Communications Commission (FCC) that could dramatically increase artificial light at night - potentially disrupting sleep, circadian rhythms and seasonal biological cycles.

In one proposal, startup Reflect Orbital plans to use large, mirrored satellites to redirect sunlight to Earth at night. While the proposal aims to illuminate solar farms, it potentially could flood entire cities with light that reaches daylight-level intensity. The FCC's public comment period for this proposal (SAT-LOA-20250701-00129) closes Friday (March 6).

The second proposal, from SpaceX, seeks approval for an orbital data center system that could include up to one million satellites in orbit. The large number of satellites can scatter sunlight, increasing overall sky brightness. The public comment period for that proposal (SAT-LOA-20260108-00016) closes Monday (March 9).

Researchers from Northwestern's Center for Circadian and Sleep Medicine and Center for Sleep and Circadian Biology (CSCB) say increasing artificial illumination at night could have wide-ranging negative effects on human health and the natural world.

Quote from Martha Hotz Vitaterna, research professor of neurobiology at Northwestern's Weinberg College of Arts and Sciences and co-director of CSCB:

"Earth was turning on its axis - causing night and day - when life began. All life forms are adapted to these cycles. Disruption by light at night threatens the well-being of not only humans but the plants and animals with which we share the planet."

Reporters can reach Vitaterna directly at [email protected] or reach out to Amanda Morris at [email protected] to schedule an interview.

Quote from Fred Turek, the Charles and Emma Morrison Professor of Neurobiology at Weinberg and co-director of CSCB:

"Plants and animals use the length of day to predict and prepare for seasonal changes. Light at night makes the short days of winter seem like the long days of summer. For example, in the 1930s, people observed that London's streetlights affected birds' seasonal reproduction. Light pollution at night disrupts vital seasonal rhythms, such as migration, growth or reproduction."

Reporters can reach out to Turek directly at [email protected] or email Amanda Morris at [email protected] to schedule an interview. Please note that Turek is traveling and may be slow to respond.

Quote from Kristen Knutson, associate professor of neurology (sleep medicine) and preventive medicine at Northwestern University Feinberg School of Medicine:

"Circadian rhythms are present in all types of organisms, ranging from bacteria to plants to animals, including humans. These rhythms synchronize physiological function to the natural light-dark cycle, which is important for overall well-being. Light at night will disrupt these rhythms, which can impair health and well-being."

Reporters can reach out to Knutson directly at [email protected] or email Amanda Morris at [email protected] to schedule an interview.

Dr. Phyllis Zee, who has conducted extensive research demonstrating the adverse health effects of light at night, also is available for interviews. Zee is the Benjamin and Virginia T. Boshes Professor of Neurology at Feinberg, director of the Center for Circadian and Sleep Medicine and chief of sleep medicine at Northwestern Medicine.

Dr. Zee can be reached directly at [email protected] or email Amanda Morris at [email protected] to schedule an interview.