Twilight is the time of day that is half way between daylight and darkness. It is when the earth’s surface is neither completely lit nor completely dark. Here in the far northern hemisphere twilight lasts much longer in the summer months and sometimes it never gets properly dark. In Norway and other countries close to the north pole it is known as the ‘Midnight Sun’.
At the end of twilight dusk falls and a bat appears in my courtyard every evening to fly in circles feeding on the night-time bugs. When I see ‘Batty’ I know it is summer.
twilight has long been popular with photographers, who refer to it as ‘sweet light’, and painters, who refer to it as the blue hour, after the French expression: l’heure bleue.