Abstract: A method and apparatus for displaying time, the day sequence for the beginning and ending of twilight, sunrise and sunset in pie-shaped section on a circular clock face. A corresponding day sequence is retrieved from a memory and presented on a circular clock face in pie-shaped sections that represent twilight, day and night for a particular coordinate position and calendar date.

Abstract: The assembly includes a keyboard (16) for operator selection of the area code or airport designation of a geographical location. A memory means (20) contains information of sunrise time, sunset time and twilight duration for each area code or airport designation selected. A counter means (30) updates and stores codes representative of the time and date. A demultiplexer (47), registers (44) and a register counter (49) accumulates the data from the keyboard and from the months (48) and days (42) counters to be sent to the memory means (20) to be decoded for selection of the necessary information. A program control (50), such as a microprocessor, accumulates the data from the memory means (20) and counter means (30) to generate a signal to and present on the video display screen (12) parallel vertical sections (60, 62, 64) representing juxtaposed hours of the day at the selected geographical location including each of light, dark and twilight hours.