Sunset

Sunset is also known as sundown. Sunset is the daily disappear of the sun below the horizon as a result of Earth rotation. In the summer season, the sun below in the northern hemisphere to the north-west, and in the southern hemisphere to the south-west. The time of sunset is defined in astronomy as the moment when the trailing edge of the sun disk disappears below the horizon.

Sunset is distinct from twilight, which has three phases, the first being civil twilight, the second phase is nautical twilight, and third is astronomical twilight. The civil twilight continues until it descends to 6 degrees below the horizon. The nautical twilight, between 6 and 12 degrees below the horizon and the astronomical twilight which is the period when the sun is between 12 and 18 degrees below the horizon.

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