What is the after hours twilight zone?

The after hours twilight zone refers to the period of time after sunset and before sunrise where the sky takes on a deep blue hue. This time is also known as nautical twilight. During this time, the stars and planets become visible, and a dim glow can be seen on the horizon. The after hours twilight zone occurs twice a day, once after sunset and once before sunrise, and its duration can vary depending on the latitude and time of year. This time period is often favored by astronomers for stargazing and astrophotography due to the clear visibility of celestial objects.