Astronomical Twilight Nautical Twilight Civil Twilight

[Daniel]

Does anyone know what these terms mean?

[Mark]

Twilight is divided into three types based on the sun's depression angle below the horizon, measuring the transition between day and night.

Civil ((0–6 degrees) below) allows for outdoor activities without artificial light.

Nautical ((6–12 degrees) below) enables marine navigation by horizon and stars.

Astronomical ((12–18 degrees) below) provides enough darkness for observing faint stars.