Iridium satellites, part of a communications constellation, carry large, flat, highly reflective antenna panels. When sunlight strikes these panels at just the right angle, they can produce a dramatic flare — a sudden burst of light that can briefly outshine Venus and appear to streak or hover in the sky. These flares are predictable and short-lived, but to an unsuspecting observer they can look startlingly like an unknown aerial phenomenon.
Astronomy outlets including EarthSky and the MTU Blackrock Castle Observatory have explicitly flagged Iridium flares as a standard explanation for UFO sightings. The pattern is consistent: a bright, fast-moving light appears without warning, lingers briefly, then vanishes — matching the classic description of many reported UFO encounters.
The phenomenon has grown beyond the original Iridium constellation. Research published via The Debrief and covered by Popular Mechanics found that SpaceX's Starlink satellites can produce "extreme flaring" under certain conditions, directly increasing UAP reports among airline pilots. Space.com similarly notes that short flashes from orbital objects — satellites and space debris alike — are now a go-to explanation for mysterious lights photographed in the sky.