Case file · Sighting
Vandenberg 'UFO' launch
At dusk on 22 December 2017 a SpaceX Falcon 9 carrying Iridium satellites rose from Vandenberg. Its sunlit exhaust plume formed a glowing jellyfish shape seen across Southern California and widely reported as a UFO.
2017 CE · 34.63, -120.61 · status: explained
The account
Twilight launches put the exhaust in sunlight while the ground is dark, producing the effect; the 'twilight phenomenon' has caused flurries of reports since the 1960s.