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Satellites should stay fainter than magnitude 7, scaled for altitude. The IAU's recommendation, set after the first Starlink launches, for keeping them out of telescope photos.

Six cameras in Ontario logged 24,812 tracks from 5,118 satellites over 36 nights in late 2024. The median satellite in every major constellation beats that ceiling, not a few bad glints. That median is over the tracks actually logged, a bright-biased slice of the sky.

By operator, share of every geometrically possible pass, a larger set than the tracked median above: Starlink 1 in 4; rocket bodies 1 in 5; Guowang/Hulianwang of China more than 1 in 2, 100 percent of those observed; OneWeb 1 in 20, the best big operator, median magnitude 7.3. Starlink still holds two-thirds of the too-bright passes.

At the Rubin Observatory, about one in three 30-second twilight photos will carry a satellite trail. Under a dark sky a person sees about 44 bright satellites at any instant, crowded into the two twilight hours.

Caveats: preprint (Oct 7 2026), not peer-reviewed; one northern site, 36 nights; faint-end numbers extrapolated from radar cross-sections.

Rayworth, Vida, Barmby et al., arXiv 2610.10834v1.