Sunset, also known as sundown, is the daily disappearance of the Sun below the horizon due to Earth& x27;s rotation. As viewed from everywhere on Earth & x28;except the North and South poles& x29;, the equinox Sun sets due west at the moment of both the spring and autumn equinoxes. As viewed from the Northern Hemisphere, the Sun sets to the northwest & x28;or not at all& x29; in the spring and summer, and to the southwest in the autumn and winter; these seasons are reversed for the Southern Hemisphere.