Overview
- A peer‑reviewed study led by ESO astronomer Olivier Hainaut, accepted for publication in Astronomy & Astrophysics, finds that current proposals for about 1.7 million new satellites would greatly brighten the night sky and could corrupt or destroy ground‑based astronomical data.
- The paper models sky brightness and streaks from planned fleets and recommends a practical ceiling of roughly 100,000 satellites that are faint enough to be invisible to the naked eye to avoid major loss of observations.
- ESO simulations show SpaceX’s proposed one‑million orbital data‑center satellites would produce dozens of trails per exposure and cause field‑of‑view data losses up to about 28% for instruments like the VLT, while wide‑field cameras such as the Rubin Observatory could be rendered unusable during illuminated periods.
- Reflect Orbital’s filing for 50,000 mirror‑satellites poses a distinct risk because each mirror could appear as bright as Venus or far brighter inside its beam and the full fleet would raise sky brightness by roughly three to four times, according to the study.
- ESO, the Royal Astronomical Society and the IAU have submitted the study as formal intervention to the U.S. Federal Communications Commission, which has received thousands of public comments and must now decide whether to approve, modify or deny the pending filings.