WASHINGTON, July 15 — A mirror satellite with a diameter of approximately 20 meters is set to launch into low Earth orbit, capable of reflecting sunlight onto a five-kilometer-wide patch of the planet at night. According to filings with the Federal Communications Commission, the approved satellite will measure approximately 20 meters in diameter. It will operate at an altitude of 600 kilometers in a sun-synchronous orbit, allowing it to pass over the same area at the same local time each day.
The design allows the satellite to illuminate a given area for up to five minutes per pass. The brightness of the reflected spot on Earth will range from 0.1 to 0.5 lux.
The lower end of that range is comparable to the light of a full moon, which measures 0.1 lux. The satellite’s total mass is estimated at 500 kilograms. Project costs are estimated at $50 million.
The funding comes from private investors and a small NASA grant, according to the filings.
How the system works
The satellite functions as an orbital mirror. Once deployed, it will catch sunlight and redirect a concentrated beam toward a targeted area on the Earth’s surface. The five-kilometer diameter of the illuminated spot suggests a relatively wide, diffuse beam rather than a tight, laser-like focus.
The 0.5 lux maximum brightness is enough for basic visibility but remains far dimmer than typical urban street lighting, which often measures 10 to 20 lux. The sun-synchronous orbit is a key design choice.
Satellites in this orbital plane cross the equator at the same local solar time on every pass. For a mirror satellite, this ensures predictable illumination windows for the same geographic region day after day. On the timeline, the FCC filing marks a regulatory milestone.
The commission’s approval clears the way for construction and eventual launch. No launch date has been specified in the filings, but the approval signals that the project has moved from concept toward hardware development.
Context and precedent
The concept of orbiting mirrors is not new. Russian engineers experimented with the Znamya space mirror experiments in the 1990s, deploying a 20-meter reflective film from a Progress cargo spacecraft. Those tests produced a brief, dim spot on the ground before the mirror tore during deployment.
The current project appears to draw on similar principles but with modern materials and attitude control systems. Sources familiar with the project note that the 500-kilogram mass is relatively modest for a satellite of this size.
The structure will likely be a lightweight reflective membrane supported by a deployable framework, similar in concept to solar sails but optimized for visible light reflection rather than propulsion. The $50 million budget places the project in the range of a small NASA science mission or a dedicated commercial rideshare launch. The involvement of private investors alongside a NASA grant suggests a public-private partnership structure, though the filings do not identify the private backers.
Potential applications and concerns
The filings describe the satellite’s capability but do not specify its intended use. Possible applications include emergency lighting for disaster zones, augmenting moonlight for nighttime construction or agricultural operations, or even artistic and entertainment purposes. The five-minute illumination window per pass limits the satellite’s utility for continuous lighting.
A single satellite can only serve one location per orbit, and the next pass would come roughly 90 minutes later as the satellite completes a full revolution around the Earth. Astronomers have raised concerns about orbiting reflectors in the past.
Light pollution from satellite constellations already complicates ground-based observations. A 20-meter mirror capable of directing a beam toward the ground could introduce additional stray light into sensitive telescopes. The 0.1 to 0.5 lux brightness is comparable to natural moonlight, but the artificial nature of the beam and its potential to appear in unexpected locations could still disrupt observations.
The satellite’s operators have not publicly addressed these concerns in the filings. The FCC approval process typically considers radio frequency interference and orbital debris mitigation but does not extensively regulate visible light emissions.
What to watch next
The next steps for the project include finalizing the satellite design, securing a launch provider, and obtaining any additional regulatory approvals needed for deployment. The small NASA grant suggests some level of government interest in demonstrating the technology, but the bulk of the funding comes from private sources whose objectives remain undisclosed. If the satellite performs as designed, it could open the door to a fleet of similar reflectors.
A constellation of mirror satellites could provide more frequent illumination passes or cover multiple locations. Alternatively, a single demonstration mission could prove the concept and then deorbit after a short operational life.
For now, the record shows a 20-meter mirror, a 600-kilometer orbit, and a $50 million price tag. The rest depends on what happens after launch.
