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To: Boogieman

The “Degree’ (angle measure)

From wiki -

The original motivation for choosing the degree as a unit of rotations and angles is unknown.

One theory states that it is related to the fact that 360 is approximately the number of days in a year.

Ancient astronomers noticed that the sun, which follows through the ecliptic path over the course of the year, seems to advance in its path by approximately one degree each day. Some ancient calendars, such as the Persian calendar, used 360 days for a year. The use of a calendar with 360 days may be related to the use of sexagesimal numbers.

Another theory is that the Babylonians subdivided the circle using the angle of an equilateral triangle as the basic unit and further subdivided the latter into 60 parts following their sexagesimal numeric system. The earliest trigonometry, used by the Babylonian astronomers and their Greek successors, was based on chords of a circle. A chord of length equal to the radius made a natural base quantity. One sixtieth of this, using their standard sexagesimal divisions, was a degree.

Aristarchus of Samos and Hipparchus seem to have been among the first Greek scientists to exploit Babylonian astronomical knowledge and techniques systematically. Timocharis, Aristarchus, Aristillus, Archimedes, and Hipparchus were the first Greeks known to divide the circle in 360 degrees of 60 arc minutes.[11] Eratosthenes used a simpler sexagesimal system dividing a circle into 60 parts.

The division of the circle into 360 parts also occurred in ancient India, as evidenced in the Rigveda


95 posted on 11/08/2019 11:38:37 AM PST by _Jim (Save babies)
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To: _Jim
Ancient astronomers noticed that the sun, which follows through the ecliptic path over the course of the year, seems to advance in its path by approximately one degree each day.

So if we were to attend geometry class on another planet, we'd be completely lost. Not withstanding the fact that if we were on another planet the LAST thing we'd want to be doing is sitting in geometry class....Biology class would be crazy.
96 posted on 11/08/2019 11:50:15 AM PST by mmichaels1970
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To: _Jim

Stop spamming the forum unless you have something actually useful to contribute. Anyone can look up articles and we have all learned this stuff way back in high school anyway.


98 posted on 11/08/2019 12:09:38 PM PST by Boogieman
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