dawnonline puzzles

Dawn, from an Old English verb dagian: "to become day ", is the time that marks the beginning of twilight before sunrise . It is recognized by the appearance of indirect sunlight being scattered in the atmosphere , when the centre of the Sun 's disc reaches 18° below the horizon . This dawn twilight period will last until sunrise (when the Sun 's upper limb breaks the horizon ), as the diffused light becomes direct sunlight .