The time after civil twilight, when the brighter stars used for celestial navigation have appeared and the horizon may still be seen. It ends when the center of the sun is 12 degrees below the horizon, and it is too difficult to perceive the horizon, preventing accurate sighting of stars. Related term: twilight
NAUTICAL TWILIGHT
Meaning of NAUTICAL TWILIGHT in English
Weather and meteorology English vocabulary. Английский словарь погоды и метеорологии . 2012