Hipparchus And The Precession Of The Equinoxes

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Trigonometry has been used for thousands of years, but many don’t know where it all began and originated. There were many individuals that contributed to the development of this area of study, which has created the official study of the relations of the sides and angles of triangles and the relevant functions of any angles. As a Greek astronomer, geographer, and mathematician, Hipparchus of Rhodes is known as the person that laid the framework for trigonometry and is famous for his incidental discovery of precession of the equinoxes.
Little is known of Hipparchus’s life, but he had a great impact on the trigonometry course we study today. He was born 190 BC in Nicaea in Bithynia, which is now Iznik, Turkey. He is listed as a famous man of
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He was the first person whose systematic use of trigonometry has documentary evidence, which is presented from Ptolemy and Theon of Alexandria. For example, he is responsible for the division of a circle into 360 degrees, the creation of one of the first trigonometric tables for solving triangles, and the precepts of trigonometry. The table showed how each degree divided into 60 minutes, which made the radius 360.60/2π = 3438 minutes and the chord function Crd of Hipparchus is related to the sine function by (Crd 2a)/2 = 3438 sin a. The table of chords, explained in 12 books, is used as a method to solve triangles without having to solve each triangle from first principles. As an astronomer, he calculated the length of the year to within 6.5 minutes. He also discovered the precession of equinoxes with a value of 46 degrees, which is fairly close to the modern number of 50.26 degrees. The precession of the equinoxes, or the gradual shift in Earth’s rotation axis, demonstrates how the earth wobbles like a top as it spins, which indicates there is a shift in point of direction of the poles over time. Hipparchus’s calculations are able to explain why the north star changes throughout a 26,000-year cycle; at some point of time it was Thuban, Beta Ursae Majoris, and the Polaris star is the north star now. In addition, he charted the sky with 850 stars and motions of the moon. These are
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