The duration between sunset and the point at which it becomes completely dark, known as dusk, can vary depending on several factors such as geographical location, time of year, and atmospheric conditions. On average, dusk typically lasts for about 20 to 30 minutes after the actual sunset time.
During this period, the sky transitions from the brighter twilight colors to a deeper blue, and eventually to darkness as the Sun's light diminishes. The exact duration of dusk can be influenced by factors like latitude, local topography, weather conditions, and the presence of clouds or atmospheric particles.
In some regions and during certain times of the year, dusk may last longer, especially in areas closer to the Earth's poles. Conversely, in tropical regions near the equator, dusk tends to be relatively short-lived due to the more rapid change in daylight hours throughout the year.
It's important to note that there isn't an abrupt transition from daylight to complete darkness. There is a gradual fading of light during dusk, and the duration can vary slightly depending on the factors mentioned earlier.