Summary
Jeju ATC and commercial airline pilots logged a bright metallic sphere hovering near active flight paths.
Detail report
Air Traffic Control at Jeju International Airport received independent reports from two commercial airline captains regarding an intensely glowing metallic sphere hovering near their assigned descent vector. Primary radar at Jeju ATC corroborated an unidentified target at 24,000 feet. The object remained completely stationary despite upper-altitude winds before executing an instantaneous vertical climb into upper cloud cover.