The position of the sun throughout the year was an important factor during ancient times, because it determines the time for doing certain activities on the farm – like sowing seeds, cattle grazing, and mundane chores like churning butter or spinning flax. Due to the absence of electricity, people during those times relied on the maximum illumination and the warmth that the sun could give, especially in cold, arid mountain ranges of Europe and the temperate summers of the Americas. This information gave the power to maximize the life-giving benefits of the sun.
Sunrise and sunset is said to happen when the geometric zenith distance of the sun is approximate to 90°. Mathematically, that meant that the center of the sun is geometrically 50 arc minutes below a parallel plane. At sea level with a smooth, clear horizon under usual atmospheric circumstances, the higher appendage of the sun will appear to hide in the horizon. The 50-arc minute geometric slump is determined from getting the sum of the mean evident radius of the sun and the average quantity of atmospheric refraction at the horizon.
The dawn of computers has made it possible to determine sunset times with the push of a button and will provide a result with the lowest possible error. These programs abound in the Internet and are an important tool for aviators, travelers and users who have plans for that important day (like weddings, get-togethers or physical activities like cycling or hiking). Almost all of these sites require the same information for the computer to calculate the data.
You have to specify your location. This is for pointing out the exact place on planet Earth where the sunset time will be calculated. This information also will help calculate the sunrise time. Fill in the date or inclusive dates where you want your sunset and sunrise times computed. Indicate the time zone of your selected location. In the United States alone, there might be several time zones for the state. If not indicated, it usually defaults to a certain time zone, causing erratic results. Express the duration of how long you’d like the program to compute the sunset and sunrise times. Sometimes, some programs would also compute for civil twilight for airplane pilots or astronomical and nautical dawn or dusk for ship captains. After putting all these data down, press the compute button and wait for the results. Most sites will allow printer friendly outputs.
The early astrologers of Asia always used their mathematical ability to determine the sun’s position. This expertise has been utilized in military tactics and in agriculture. Primeval priests relied on the rising and setting of the sun to determine when to ask the gods for favors and when to sacrifice. With the sunrise and sunset, these authority figures were able to maximize their schedule for the day. There is no sight more relaxing than seeing the warm glow of the sunset promising a relaxing night ahead after a day of hectic work.