CSE Reply Comment to the FCC on Reflect Orbital's application to operate a prototype solar reflector (ICFS File No. SAT-LOA-20250701-00129)

March 30, 2026

Before the

FEDERAL COMMUNICATIONS COMMISSION

Washington, D.C. 20554

)

In the Matter of: Reflect Orbital Inc.       ) ICFS File No. SAT-LOA-20250701-00129

            )                    via ICFS Electronic Filing

REPLY COMMENTS OF THE CENTER FOR SPACE ENVIRONMENTALISM

I. THE “PATHFINDER” FALLACY: CONNECTED AND CUMULATIVE ACTIONS

The applicant repeatedly asserts that the record is “muddled” by concerns regarding a full-scale constellation, arguing that the Commission should only consider the “particular action” of a single satellite.[2] This is a strategic attempt to bypass the requirements of the National Environmental Policy Act (NEPA). Reflect Orbital’s own public business model depends on a constellation of thousands of mirrors to achieve its stated “Sunlight as a Service” goals.[3]

A “test-study-adapt” model[4] is not a substitute for a comprehensive Environmental Impact Statement (EIS). NEPA requires that agencies consider “connected actions” and “cumulative impacts.” Granting authority for a prototype that exists solely to validate a constellation of thousands, which will collectively inject massive amounts of soot and alumina into the stratosphere[5] and functionally erase the natural night sky for millions, is an action with significant environmental consequences that cannot be ignored through a “single satellite” defense.

The scale of this environmental impact is substantiated by high-fidelity radiance calculations that evaluate the reflected sunlight from non-perfectly flat orbital mirrors. These calculations, which account for solar limb darkening and atmospheric transmittance, demonstrate that even a single satellite at an altitude of 625 km produces an apparent brightness that exceeds all natural nighttime celestial objects. As illustrated in Figure 1, a mirror at the zenith produces a peak Johnson V magnitude of approximately -14.5, which is roughly six times the apparent brightness of the full moon; see Figure 1.

Crucially, this extreme brightness is not confined to a narrow point. Due to surface unevenness (modeled as root-mean-square tilts, σ), the reflected beam remains significantly brighter than a full moon at distances of several kilometers from the target center. Consequently, a single pass from such a satellite could effectively eliminate the natural night sky across hundreds of square kilometers, simultaneously impacting millions of residents.

The Applicant’s assertion that its mission is “properly excluded” from NEPA review[6] ignores the specific regulatory safeguard designed for unprecedented actions. The Commission is empowered to require an Environmental Assessment (EA) for an otherwise excluded action if it “may have a significant environmental impact.”[7] Reflect Orbital’s intentional reflection of concentrated sunlight into the night sky represents exactly such an "extraordinary circumstance," distinguishing it from the incidental reflectivity of communication satellites cited by the Applicant.[8]

Furthermore, the Applicant’s comparison of EARENDIL-1 to the International Space Station (ISS) is technically flawed.[9] Unlike the ISS, which acts as a diffuse reflector primarily visible during twilight, the EARENDIL-1 is a specular mirror designed for active nighttime illumination. As substantiated by the radiance calculations below, EARENDIL-1 can reach a peak apparent illuminance approximately six times that of a full moon, a level that the ISS never approaches and which fundamentally alters the nighttime environment. Similarly, the Applicant’s attempt to minimize the hazard by comparing EARENDIL-1 to the larger Znamya-2 experiment[10] is scientifically misleading; 'mirror diameter' is a poor metric for retinal safety as it fails to account for Znamya’s segmented geometry (roughly 70% filling fraction) and the vastly superior specular efficiency of modern materials, which ensure that EARENDIL-1 delivers an equivalent or even greater optical intensity than its predecessor.[11]

Granting this application would establish a dangerous regulatory precedent by permitting private entities to alter global nighttime conditions before the Commission has established a proper framework. As noted in the record,[12] the Commission should defer action on this novel technology until it completes its ongoing rulemaking in WT Docket No. 25-217,[13] which specifically addresses the modernization of NEPA procedures for the second ‘Space Age’.

II. RETINAL HAZARDS: CHALLENGING THE APPLICANT'S SAFETY CLAIMS

The applicant attempts to dismiss concerns regarding solar retinopathy by citing ICNIRP point source exposure limits, claiming that viewing EARENDIL-1 with aperture aids up to 12 inches is “acceptable.”[14] This assessment is dangerously incomplete. For example, the Applicant argues that for small angular sizes (under 25-50 μm on the retina), the mirror should be treated as a point source. But when viewed through a telescope, the effective exposure still exceeds or approaches the ICNIRP threshold limits.

While ICNIRP exposure thresholds are intended to be conservative, their interpretation is nuanced and limited by the assumptions of the underlying models.[15, 16] For example, we calculate that the exposure from a large Reflect Orbital mirror (even at the 18m × 18m prototype size) seen through common astronomical instruments, such as a 30-cm (12-inch) telescope at 50× magnification, presents a potential hazard.[17] In these scenarios, the irradiance at the eye, while lower than direct illumination by the Sun, can still be within two orders of magnitude below solar levels; see Figure 2. For the 18 m × 18 m EARENDIL-1 mirror seen through a 12-inch telescope at 50× magnification, surpassing the injury threshold requires about one minute of exposure, which is well within the duration of a single overpass of the satellite.

The Applicant’s dismissal of the risks identified by Laframboise and Chou[18] relies on a misleading application of ICNIRP guidelines. The Applicant argues that because the retinal image of the 18 m mirror is less than 25 μm, it should be treated as a “point source” to which extended-source damage models do not apply. This ignores the fundamental reality of astronomical observation: any magnification greater than 35×, standard for even entry-level amateur telescopes, renders the satellite an extended source on the retina.

Furthermore, the Applicant fails to disclose the critical technical parameters underlying the safety claims, such as the assumed magnification, the ratio between the telescope’s exit pupil and the observer’s pupil, or the specific atmospheric and geometric conditions used in their models. These factors are decisive in determining effective retinal exposure. While the Applicant asserts that 12-inch optics are "acceptable," our high-fidelity calculations for the 18 m prototype demonstrate that photochemical damage thresholds (specifically Blue-light Type II hazards) can be surpassed during sustained exposures of 60 to 100 seconds when using such an instrument. By providing no verifiable details, the Applicant’s safety claims remain technically unsubstantiated and fail to account for the foreseeable "worst-case" scenarios that safety standards like ICNIRP are designed to prevent.

Lastly, the Applicant’s characterization of the light as “de minimis moonlight” is internally contradictory. As scientific commenters have noted, the Applicant has failed to contest technical descriptions in the record characterizing the source as “significantly brighter than the full moon" and a "glaring, star-like source.”[19] This unresolved point-source brightness, rather than a diffuse lunar glow, is precisely what drives the heightened retinal hazard.

III. THE INADEQUACY OF “GEOFENCING” AND “TRANSPARENCY”

Reflect Orbital introduces three “guiding principles” (Controllable, Transparency, and Avoidable) as self-policing mitigations.[20] Specifically, they propose “geofencing” to avoid observatories.[21] This proposal is fundamentally flawed for two reasons: (1) it shifts the burden of safety and “avoidance” onto the astronomical community and the public; and (2) geofencing only addresses the direct beam center.

The Applicant's “geofencing” strategy[22] is technically insufficient because it addresses only the direct beam center. It fails to account for atmospheric scattering and the resulting diffuse skyglow. Rayleigh and Mie scattering ensure that light directed at a target area produces diffuse radiation visible across hundreds of kilometers, degrading the signal-to-noise ratio for sensitive observatories even if they are outside the direct beam.[23] Without a comprehensive “spillover” model, the Applicant cannot claim that their exclusion zones actually preserve the darkness of the night sky for neighboring communities or observatories. Additionally, the Applicant has failed to disclose the satellite’s default orientation in the event of a power or control failure. Without a fail-safe orientation that prevents reflection, the public faces the risk of sustained, uncontrolled illumination for the duration of EARENDIL-1's orbital life.[24]

Furthermore, the Applicant’s dismissal of “trespass” and “nuisance” as purely civil matters[25] misinterprets the Commission’s primary duty. Under the Communications Act, the Commission is legally required to ensure that any licensed activity serves the “public interest, convenience, and necessity.”[26] A technology that by design projects unwanted, intense light onto private property and into homes constitutes a systemic public nuisance that is fundamentally at odds with the public interest.

IV. THREATS TO PLANETARY DEFENSE AND NEO DETECTION

The proposed mission poses a direct threat to federally mandated planetary defense objectives. Even modest increases in sky background brightness can measurably degrade the completeness of the Congressionally required survey for Near-Earth Objects (NEOs) conducted by the Vera C. Rubin Observatory.[27] The Applicant’s failure to engage with peer-reviewed literature (e.g., Kandula et al. 2025[28]) analyzing how increased sky brightness reduces detection thresholds for faint, near-threshold asteroids highlights the inadequacy of their "test-study-adapt" approach. The Commission should not grant this license without formal consultation with the NSF and DOE regarding impacts on this $500 million federal investment in planetary safety.

V. ORBITAL SAFETY AND UNCONTROLLED RE-ENTRY

Finally, the applicant characterizes orbital debris concerns as issues of “general applicability” that should be reserved for future rulemaking.[29] We disagree. The specific design of EARENDIL-1, specifically the survival of titanium propellant tanks during re-entry, presents a concrete, localized risk to public safety.[30, 31] The Applicant’s own data suggests these tanks will impact the ground with a kinetic energy of 2,544 J.[32, 33] The Applicant’s own modeling reveals that the associated casualty risk is 1:119,400,[34] which is perilously close to the Commission's 1:10,000 safety threshold. Crucially, the ODAR admits that safer, demisable tank materials were rejected in favor of titanium due to “lead time” and integration schedules.[35] The Commission should not allow an Applicant to prioritize its commercial launch timeline over the physical safety of the public. Furthermore, the ODAR relies on a "final orienting maneuver" for safe deorbit,[36] yet provides no failure-mode analysis for the collision risk posed by an 18m mirror if attitude control is lost during the mission. These are specific hazards of this spacecraft that demand immediate regulatory accountability, not a deferral to broad policy discussions.

VI. MANDATORY ENVIRONMENTAL REVIEW UNDER 47 C.F.R. § 1.1307(a)

The Applicant’s reliance on a broad categorical exclusion for satellite operations fails to account for the mandatory environmental review triggers codified in 47 C.F.R. § 1.1307(a). Specifically, § 1.1307(a)(3) requires the preparation of an Environmental Assessment (EA) for any facility that “may affect listed threatened or endangered species or designated critical habitats.”[37] While the physical hardware of the EARENDIL-1 satellite is located in orbit, the primary operational “facility” of the mission is a concentrated beam of reflected sunlight that physically penetrates terrestrial habitats. As substantiated by the radiance models in Section I, this beam can reach intensities considerably brighter than that of a full moon. This intentional environmental intervention directly disrupts the biological rhythms and nesting behaviors of protected species whose survival is inextricably linked to the preservation of the natural light-dark cycle.

The Commission’s legal obligation to conduct this review is further underscored by Section 7 of the Endangered Species Act (ESA), which requires federal agencies to ensure that their actions are not likely to jeopardize the continued existence of any endangered or threatened species.[38] The Government Accountability Office (GAO) has explicitly criticized the Commission’s continued reliance on environmental rules from 1986 that focus almost exclusively on terrestrial infrastructure (like towers), noting that the Commission has not sufficiently documented its decision to apply categorical exclusions to modern satellite systems with significant terrestrial environmental footprints.[39] Furthermore, the D.C. Circuit Court of Appeals highlighted that the administrative record must reflect a rigorous adherence to NEPA when orbital actions have clear terrestrial consequences.[40] This requirement for a robust administrative record was recently reaffirmed,[41] where the Court emphasized that the Commission must “reasonably explain” its environmental determinations and cannot rely on conclusory assertions to dismiss the impact of satellite constellations on the nighttime environment. Given the unprecedented and intentional nature of the Applicant’s proposed action, a categorical exclusion is legally insufficient, and a formal EA is required to fulfill the Commission's statutory duties.

VII. ENVIRONMENTAL JUSTICE AND HUMAN RIGHTS

The Commission must consider the environmental justice (EJ) implications of licensing “forced illumination” technology, which represents a novel and pervasive environmental stressor. Unlike natural celestial light, the Applicant’s system allows for selective, switchable illumination that can be directed at specific populations without their consent. Decades of EJ research establish that the unequal distribution of environmental hazards like light pollution is a primary driver of health inequity.[42] Recent distributive analyses of light pollution in the United States demonstrate that marginalized and low-income communities are already disproportionately burdened by artificial light at night (ALAN). Specifically, research shows that the most socially vulnerable communities experience ALAN levels nearly 2.5 times higher than those in the least vulnerable areas, and that Black, Hispanic, and Asian Americans are exposed to neighborhood light pollution at rates approximately double those of white Americans.[43]

This disproportionate exposure is directly linked to adverse health outcomes, including sleep disorders, obesity, and increased risks for breast and prostate cancers. Licensing an orbital system such as that the Applicant proposes that can intensify these existing burdens contradicts the principle that access to a natural environment, including the natural night sky, should be an equitably distributed public good rather than a luxury for the privileged few.[44]

Furthermore, the potential for “Sunlight as a Service” to be utilized for surveillance or as a form of extra-judicial policing represents a profound threat to human rights and civil liberties. For communities already subject to over-policing, the ability of a private entity or government client to unilaterally eliminate the sanctuary of darkness constitutes a significant civil rights concern. Under Executive Order 12898, the Commission is required to identify and address these disproportionately high and adverse human health or environmental effects.[45] Given the potential for this technology to be used as a tool of coercion or intimidation, it is fundamentally at odds with the “public interest” standard the Commission is bound to uphold.

VIII. CONCLUSION

Reflect Orbital’s response confirms that it views the statutory requirements of environmental and safety law as a mere “administrative roadblock.”[46] However, the administrative record demonstrates that the proposed action, both as a highly hazardous standalone prototype and as a precursor to a massive constellation, threatens irreversible harm to global biodiversity, public safety, and the cultural heritage of the night sky. The Applicant’s failure to address the mandatory triggers for environmental review under 47 C.F.R. § 1.1307(a) and (c), as well as its disregard for the Commission’s duties under the Endangered Species Act, is disqualifying.

Crucially, the Commission must not allow the Applicant to use a single "pathfinder" application as a Trojan horse to establish a regulatory precedent for the commercial illumination of the night sky. Approving the EARENDIL-1 satellite without environmental review effectively opens the door to the Applicant's stated end-goal: a constellation of 54-meter reflectors that will industrialize the natural nighttime environment.

The Commission cannot fulfill its mandate to serve the “public interest, convenience, and necessity” by permitting the intentional, large-scale alteration of the nighttime environment based on the Applicant’s insufficient self-policing principles. To uphold its statutory duties under the Communications Act, NEPA, and the ESA, the Commission must reject the Applicant’s request for a categorical exclusion. The CSE respectfully urges the Commission to require the preparation of a comprehensive Environmental Assessment (EA) or Environmental Impact Statement (EIS) as a prerequisite for any licensing of orbital illumination technology.

Respectfully submitted,

John C. Barentine, Ph.D. 

on behalf of the Center for Space Environmentalism

Correspondence may be directed to: admin@spaceenvironmentalism.org

Notes

[1] Reflect Orbital Inc., Consolidated Opposition and Response to Comments of Reflect Orbital Inc., ICFS File No. SAT-LOA-20250701-00129 (Mar. 24, 2026). 

[2] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 3. 

[3] Reflect Orbital, Vision for 2030 and 2035 Constellations. https://www.reflectorbital.com/ (last visited Mar. 25, 2026). 

[4] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 2. 

[5] C.M. Maloney et al., Investigating the Potential Atmospheric Accumulation and Radiative Impact of the Coming Increase in Satellite Reentry Frequency, 130 J. Geophysical Rsch.: Atmospheres e2024JD042442 (2025). https://doi.org/10.1029/2024JD042442 

[6] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 9. 

[7] 47 C.F.R. § 1.1307(c) (2024). 

[8] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 11. 

[9] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 13. 

[10] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 12. (in which they allege that the irradiance of Znamya and the Sun are identical) 

[11] The Applicant's comparison to the 25 m diameter Znamya-2 experiment is an oversimplification that ignores the "filling fraction" and reflective efficiency of the two designs. While Znamya-2 had a larger nominal diameter, its segmented geometry resulted in an effective reflective area of only ~70% (approximately 343 m2). This is nearly identical to the 324 m2 solid area of the 18 m EARENDIL-1 prototype. When factoring in the vastly superior specular efficiency of modern reflective coatings (potentially 90% or higher) compared to the estimated 50% efficiency of the Znamya materials, the EARENDIL-1 prototype is capable of delivering a peak retinal irradiance that matches or exceeds its larger predecessor. 

[12] Walter W. Golay, Response to Reflect Orbital’s Consolidated Opposition and Response to Comments, ICFS File No. SAT-LOA-20250701-00129, at 4 (Mar. 26, 2026). 

[13] Federal Communications Commission, Expediting Initial Revision of Environmental Rules, WT Docket No. 25-217 (2025). 

[14] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 12. 

[15] Comments of the Center for Space Environmentalism In the Matter of: Reflect Orbital Inc., ICFS File No. SAT-LOA-20250701-00129, at 2 (filed Mar. 4, 2026). 

[16] Int'l Comm'n on Non-Ionizing Radiation Prot., ICNIRP Guidelines on Limits of Exposure to Laser Radiation of Wavelengths between 180 nm and 1,000 μm, 105 Health Phys. 74 (2013). https://doi.org/10.1097/hp.0b013e3182983fd4 

[17] Calculations were made assuming unaided-eye observations of single, well separated satellites (i.e., seen as distinct, well-resolved bright spots on the sky). The situation could be different if observing with instruments and/or, if several mirrors are very close angularly and are perceived as a single spot by the eye of the observer. The results depend on several parameters: satellite attitude (cross section as seen from the Sun/observer), orbital height (assumed to be 625 km), mirror reflectance (assumed to be 0.9) and others (e.g., atmospheric extinction). Rayleigh optical depths were drawn from P.M. Teillet, Rayleigh Optical Depth Comparisons from Various Sources, 29 Appl. Optics 1897 (1990). https://doi.org/10.1364/AO.29.001897 The spectral dependence of aerosol parameters, with both Angström exponents equal to 1.0 (for absorption and scattering) and no individual molecular absorption lines, is from A. McComiskey et al., Direct Aerosol Forcing: Calculation from Observables and Sensitivities to Inputs, 113 J. Geophysical Res. D09170 (2008). https://doi.org/10.1029/2007JD009170 

[18] J. G. Laframboise & B. R. Chou, Space mirror experiment: A potential threat to human eyes, 94 Journal of the Royal Astronomical Society of Canada 237 (2000). 

[19] W. Golay, Response to Reflect Orbital’s Consolidated Opposition and Response to Comments, supra note 11, at 3. 

[20] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 14. 

[21] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 14. 

[22] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 2. 

[23] W. Golay, Response to Reflect Orbital’s Consolidated Opposition and Response to Comments, supra note 11, at 3. 

[24] W. Golay, Response to Reflect Orbital’s Consolidated Opposition and Response to Comments, supra note 11, at 5. 

[25] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 16. 

[26] Communications Act of 1934, 47 U.S.C. § 303(g) (directing the Commission to "encourage the larger and more effective use of radio in the public interest"). 

[27] George E. Brown, Jr. Near-Earth Object Survey Act, Pub. L. No. 109-155, § 321, 119 Stat. 2895, 2922 (2005). 

[28] P. Kandula, et al., Report on LEO Satellite Impacts on Ground-based Optical Astronomy for the Rubin Observatory LSST, arXiv:2509.19758 https://arxiv.org/abs/2509.19758 [29] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 15. 

[30] Reflect Orbital Inc., Exhibit B: Orbital Debris Assessment Report (ODAR), ICFS File No. SAT-LOA-20250701-00129, at 13 (filed July 31, 2025). 

[31] Reflect Orbital Inc., Exhibit A: Technical Annex for EARENDIL-1, ICFS File No. SAT-LOA-20250701-00129, at 1 (filed July 31, 2025). 

[32] Letter from Fed. Commc'ns Comm'n to Reflect Orbital Inc., ICFS File No. SAT-LOA-20250701-00129, at 2 (Dec. 4, 2025). 

[33] Reflect Orbital Inc., Exhibit B: Orbital Debris Assessment Report (ODAR), ICFS File No. SAT-LOA-20250701-00129, at 13 (filed July 31, 2025). 

[34] Reflect Orbital Inc., Orbital Debris Assessment Report (ODAR), supra note 30, at 13. 

[35] Reflect Orbital Inc., Orbital Debris Assessment Report (ODAR), supra note 30, at 13. 

[36] Reflect Orbital Inc., Orbital Debris Assessment Report (ODAR), supra note 30, at 8 (Section 3: "Passivation Plan"). 

[37] 47 C.F.R. § 1.1307(a)(3) (2024). 

[38] 16 U.S.C. § 1536(a)(2) (Section 7 of the Endangered Species Act). 

[39] U.S. Gov’t Accountability Off., GAO-23-105005, Satellite Licensing: FCC Should Reexamine Its Environmental Review Process for Large Constellations of Satellites (2022). https://www.gao.gov/products/gao-23-105005 

[40] Viasat, Inc. v. FCC, 47 F.4th 769 (D.C. Cir. 2022), at 774 (analyzing whether the administrative record contained sufficient detail to evaluate terrestrial environmental risks from orbital operations under NEPA). 

[41] Int’l Dark-Sky Ass’n v. FCC, No. 22-1337, slip op. at 12-14 (D.C. Cir. 2024) (explaining that the Commission’s environmental conclusions must be supported by a reasoned analysis in the record). 

[42] Q. Xiao et al., Artificial Light at Night and Social Vulnerability: An Environmental Justice Analysis in the United States, 113 J. Env't Rsch. 109959 (2023). 

[43] C. Nadybal et al., Light Pollution Inequities in the Continental United States: A Distributive Environmental Justice Analysis, 113 Env't Rsch. (2020). 

[44] Center for American Progress, The Nature Gap: Communities of Color and Those With Low Incomes Are Bearing the Brunt of America's Nature Loss (2020). 

[45] Exec. Order No. 12898, 59 Fed. Reg. 7629 (Feb. 11, 1994). 

[46] Consolidated Opposition and Response to Comments of Reflect Orbital Inc., supra note 1, at 8.