California startup’s Plan for Orbital Sunlight Mirrors Raises Concerns
A California-based startup,Reflect Orbital,is proposing a novel solution to energy needs: illuminating Earth with sunlight reflected from a constellation of orbiting mirrors. The company claims its system will deliver “continuous, reliable access to energy, day or night, to increase power generation.” this ambitious project has already garnered significant investment and a $1.25 million Small Buisness Innovation Research contract from the U.S. Air Force.
The concept, likened to using a mirror to direct sunlight, involves deploying a large number of reflective satellites. However, astronomers are voicing concerns about the feasibility and potential consequences of such a system.
Michael J. I. Brown of Monash University and Matthew Kenworthy of Leiden University recently detailed their analysis in The Conversation, explaining that the immense distance and size of the sun would cause the reflected beam to spread, resulting in a light source approximately 15,000 times dimmer then midday sun upon reaching Earth’s surface – though still brighter than a full moon. They calculate that achieving just 20% of midday sun illumination would require approximately 3,000 of the proposed 54-meter (177-foot) satellites. To provide continuous illumination, they estimate over 4,000 satellites would be necessary.
Beyond the sheer scale of the project, potential malfunctions pose a risk. As explained by Daniel Eggl, a researcher at Harvard’s Center for Astrophysics, a collision with space debris or a meteorite could cause a satellite to tumble, transforming it into “a gigantic lighthouse that is uncontrollably illuminating parts of the earth.”
The proposed constellation also raises serious concerns about light pollution. Astronomers already face increasing challenges due to rising global light pollution levels, which have been increasing roughly 10% per year since the introduction of LED lights. Eggl warns that the mirrors would drastically increase sky brightness, effectively creating a “full Moon every night,” which would be “devastating to astronomy” and hinder the observation of faint celestial objects.
The impact extends beyond astronomical research. Light pollution disrupts the natural day-night cycles of numerous animal species. David Smith, advocacy and social change manager at invertebrate charity BugLife, told Space.com that artificial light “interferes with the circadian rhythms, the physiology, and the behavioural patterns of countless species.”
Reflect Orbital’s submission for a license from the Federal Communications Commission (FCC) is currently pending. Eggl hopes regulators will carefully consider the scientific community’s concerns, stating, “given what they propose, I see no clear way this cannot be extremely disruptive for all sorts of things.”
