The Heavens declare the geometrical beauty of Creation ! Geometry is derived from Jya mithii, as the Indian mathematician, Brahma Gupta, called 360/72 = 5 degrees a Jya. His Book of Tan Tables. Sparsa Jyakkal, gives accurate tan values for every 5 degrees. Tan is used for calculating the longitudes of planets, in the Third Reduction, Reduction to the Geocentric Coordinate System, the other two being Reduction to Heliocentric and Ecliptic Systems !