As discussed earlier, the equator and the point from which the two ends are projecting out from the globe are called axis and global axis. The sky revolves on this axis like a wheel. The circle formed by this revolution of the sky is known as the great circle. Within this great circle there are all celestial bodies, including moon, sun and the earth, which move as per their determined duration. It is this great circle in which the annual revolution of Sun takes place. When the sun enters this circle day and night become equal. Therefore, this circle is also called equinox. This imaginary circle divides the natural sky into two equal halves from the east to the west. The northern hemisphere of this circle is known and perceptible while the southern hemisphere is imperceptible. However, it is visible at the Equator. The sun happens to arrive at this circle twice in a year. Once in the first house Aries (Megh rashi) and then in the house of Virgo (Kanya Rashi). On the basis of the equinox, observers have postulated another circle which is the route of the sun’s journey and it has been named as Zodiac.
It consists of 12 houses or Lagan. This circle which is situated nearly vertical on the equator and exactly parallel to the path of the sun is revolving like a wheel around the seven skies in a particular area of the Heaven is passing by the equator a bit slanted. The sun always performs its journey y stage by stage through this very circle and completes its course in one year. When the sun touches each of the two points of intersection, day and night become equal everywhere. The two points are then called points of equilibrium. The point which the sum passes to become indeed to the north is called spring equilibrium. It is the Mekh Rashi or a house of Aries. Another point facing it which the sum passes by to become inclined to the south is called autumnal equilibrium. It is Tula Rashi or a house of Libra. The sun always revolves within this circle. These stages of the sun art called a sum route circle.
Dr. A. Shanker
www.ShankerStudy.com
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