A peer-reviewed number for orbital glare turns Reflect Orbital's demo into a regulatory test

A paper accepted for publication in Astrophysical Journal Letters puts figures on how far Reflect Orbital's beamed sunlight would spread past the customer who ordered it, concluding that a combined beam aimed at a patch five kilometers across would still be visible as a glow above the horizon up to 80 kilometers away ^[5][9]. That matters because the Federal Communications Commission approved the company's demonstration launch in July, which makes the test satellite the first practical case of whether orbital brightness is regulated by anyone at all ^[3][1].

The numbers are the point. Miroslav Kocifaj of the Slovak Academy of Sciences and colleagues calculate that inside the intended five-kilometer target circle, one satellite would appear roughly 40 times brighter than the full moon, and that at 14 kilometers from the beam center it would still be as bright as the full moon ^[5][6][7]. That second figure describes an area about 31 times larger than the zone being sold light ^[19]. The 80-kilometer glow radius covers something on the order of a thousand times the target area ^[20]. Kocifaj's summary is that the damage extends far beyond the target area ^[10].

Scale compounds it. Combining 400 satellites, which the company eventually plans to do, would produce light as bright as 10,000 full moons inside the five-kilometer patch, or 2.4 percent of the brightness of the sun ^[8]. Those 400 are 0.8 percent of the up to 50,000 satellites, each 54 by 54 meters, that Reflect Orbital says it wants to fly ^[2][21]. The satellite launching this year, Eärendil-1, carries an 18-by-18-meter mirror ^[1]. The stated uses are prolonging daylight for solar panel charging, emergency response, and military activity, from highly inclined near-polar orbits that catch sunlight before sunrise and after sunset ^[4][16].

CEO Ben Nowack disputes the paper, saying some assumptions are simply inaccurate and that the company's safeguards, including exclusion zones, already account for scattering ^[13]. He says Reflect Orbital has engaged substantively with astronomers, environmental researchers, and scientists, and that their feedback has informed its technology and operational plans ^[14]. Kocifaj's response is that the company has published no numbers, no description of its model, no assumptions, and no data, leaving nothing to engage with technically ^[15]. Olivier Hainaut of the European Southern Observatory, who previously modeled the beams as brightening the sky worldwide by up to 300 percent, says the new results are unsurprising but useful and that the modeling group knows what it is doing ^[11][12]. Samantha Lawler of the University of Regina puts the astronomy position flatly: this is incompatible with dark skies ^[18].

The regulatory question is now live. In August a group including DarkSky International and the American Bird Conservancy asked the FCC to review its approval of Eärendil-1, raising aviation and wildlife effects alongside astronomy ^[17].

Watch whether the FCC treats brightness as within its remit or as outside a licensing decision made on spectrum grounds ^[3][17]. Watch whether Reflect Orbital publishes a scattering model with numbers rather than assurances, since that is the only thing that would settle the dispute on its merits ^[13][15]. And watch the demonstration itself: a single 18-meter mirror is a measurable object, and ground measurements of its glare will either support or undercut the 40-moons figure before the constellation is built ^[1][6].