Solar Geometry Basics
The times of sunrise and sunset depend on your latitude, longitude, date, and altitude. The Earth's axial tilt (23.44 degrees) causes the sun's path across the sky to change throughout the year, producing longer days in summer and shorter days in winter.
Types of Twilight
There are three types of twilight defined by the sun's angle below the horizon: civil twilight (0 to 6 degrees), nautical twilight (6 to 12 degrees), and astronomical twilight (12 to 18 degrees). Each has practical significance for visibility and navigation.
Golden Hour and Photography
The golden hour occurs when the sun is low on the horizon, producing warm, soft, directional light. Professional photographers and cinematographers plan shoots around this window for its flattering quality of light.
Day Length Variation
At the equator, day length remains close to 12 hours year-round. As you move toward the poles, the difference between summer and winter day lengths increases dramatically. Above the Arctic and Antarctic circles, the sun can stay above or below the horizon for 24 hours.
