Civil Twilight app analytics for October 21

A guide to sun and moon data for pilots and aviation enthusiasts. Easily determine where and when rises and sets will occur during flights and estimate the flight duration between the end of evening civil twilight and the beginning of morning civil twilight. Quickly compute daily solar and lunar almanac data, including moon phases and eclipses, for over 72,000 airports. Also calculate instantaneous sun and moon data to help with assessing airfield lighting conditions.