Cool, for the curious,

Flying insects use moonlight to navigate. Since the moon is always above them, they orient themselves so that the light shines on their backs. That’s how they stay upright in flight.

Moonlight contains ultraviolet (UV) and infrared wavelengths because it is merely reflected sunlight. Insects cue on UV, believing it to be the moon. When artificial lights transmit UV they look like moonlight so insects orient their backs to it. Consequently they circle the light and even flip upside down when the artificial light is pointing up to the sky!

Incandescent lights transmit UV but LEDs do not. Insects are far less attracted to LED.