Astronomers are raising alarms about planned satellite constellations that could create a bright artificial band circling Earth, visible from every point on the planet after dusk and before dawn.
What Happened
Multiple companies including SpaceX, Starcloud, Cowboy Space, Orbital and Blue Origin have applied to the U.S. Federal Communications Commission for licenses to launch more than a combined million data center satellites, according to reporting by Space.com. Additionally, California-based Reflect Orbital received FCC approval on July 10 to fly its first orbital mirror satellite—a 60-by-60-foot demonstration craft named Eärendil-1 expected to launch before year's end—as part of plans for a constellation of 50,000 orbiting mirrors.
Hugh Lewis, professor of astronautics at the University of Birmingham in the U.K., explained that accommodating these high numbers would require stacking constellations along the terminator line—the boundary between day and night—creating what astronomers describe as an artificial "Saturn's ring" effect. Samantha Lawler, an astronomer at the University of Regina in Canada, and her colleagues modeled several proposed fleets including SpaceX's Starmind data center constellation, Blue Origin's Project Sunrise, and Cowboy Space's Stampede constellation.
Why It Matters
Lawler's visualizations show that satellites from these constellations would not only outshine visible stars but could actually outnumber them in the night sky. The ring would pass overhead at consistent times—between 6 and 8 p.m. and just before dawn—as Earth rotates under the terminator orbit, with winter nights affected more severely than summer ones due to viewing geometry. Lawler noted that scattered light from the ring could continue brightening the sky for up to two hours after the satellites sink below the horizon, similar to how sunlight persists after sunset.
"It would make our taxpayer-funded telescope time much less effective," Lawler said in the Space.com report. "We could do a lot less science for the same cost." The proposed orbital data centers and Reflect Orbital's mirrors both rely on constant solar exposure, requiring orbit along the dawn-dusk line rather than distributed coverage like existing Starlink constellations.
The Bottom Line
The proposals remain in various stages of regulatory review. Lawler's modeling is based on publicly available data and has not yet been peer-reviewed; she cautioned it may not reflect precise technical specifications of the satellites involved.