What To Know About Sunsets

By Antoinette Quinn


Sunsets, also known as sundowns, describe the daily occurrence that is the Sun disappearing below the western horizon. This natural behavior is the result of a rotating Earth. Many people enjoy watching the star go down because of the beautiful atmosphere that is created, including the intense red and orange colors.

Sunset, in astronomy, is defined as the moment in time when the trailing part of the Sun disappears below the horizon line. The light that comes from this setting process is distorted by the horizon as a result of atmospheric refraction. This is what makes it seem as though the sundown is taking place when the disk is far below its horizon.

This is different from dusk, which is the period in which the sky has reached complete darkness. This takes place once the start is approximately 18 degrees below the horizon. Twilight is the time between sundown and dusk. Areas that are located south of Antarctic Circle or north of Arctic Circle do not have sunset or sunrise one day in the year. This is because of the polar day or polar night lasting for 24 hours.

Astronomer Nicolaus Copernicus, from the sixteenth century, was the first individual to provide the world with a mathematical formula to support the theory that the Earth moves. Previously, there was a widely held belief that the Sun moves. Nowadays, people accept the model set forth by Copernicus and know that our Sun does not move at all.

The time for the Sun to go down will vary throughout the year. It is also based on the position of a viewer on Earth. That is, the elevation level, latitude and longitude of a particular location. Changes in sunset timing, whether small or noticeable, occur because the axial tilt of our planet, its revolution paired with the Moon, rotation and its orbital movement around the Sun.

During the winter and spring, the days are longer and the sundown takes place at a later time every day until the last sunset, which takes place after June 21, the summer solstice. In the Northern Hemisphere of the planet, last June or the early half of July is when the latest sunset occurs. Very rarely does this take place on the summer solstice, but it is all dependent on latitude. Likewise, the early sunsets do not usually occur on the winter solstice date, but often weeks in advance. Usually this is during late part of November or early in December, depending on the latitude.

This same phenomenon takes place in the Southern Hemisphere, but the dates are reversed. The early sunsets occur before the summer solstice in winter and the latest of sunsets take place after the winter solstice in summer. Still, it all depends on the exact latitude.

Sunsets are loved because of the beautiful changes they bring out the atmosphere. They are known for bringing out intense and brilliant colors in the clouds, Sun and sky. The duration and time of sundown is dependent on latitude, elevation and longitude of an individual. Changes in sundown take place as a result of revolutions, rotation, tilt and movement of Earth.




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