Astronomy and Cosmology

Author(s): L C Jain
Publisher: Rajasthan Prakrit Bharti Sansthan Jaipur

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ZODIAC
East
Past
part denim
-
Celent West
I shifting
horror
Present Cele
ECLIPTIC
qualor
Right
Ascension
The above diagram shows how the Vernal equinox goes on shifting (from V to W), along the ecliptic ( the path of the Sun ), and how it makes change in right ascension and declination of a star.
PANCANGA Certain technical terms used in calendar :
Pancānga is the name given to Indian calendar as it comprises of five types of information which is either collected or calculated on the basis of observations of heavenly bodies and certain theories or formulas developed in due course of time for mechanical manipulation of the data.
Before one goes into details of motion of heavenly bodies, usually kinematical in ancient texts, one has to be familiar with the terms frequently used in advanced theories of astronomy gradually evolved & developed by the ancient people for practical purposes of growing crops, regularizing duties, economizing time and then optimizing their own operations. This might have led them to speculative sports and games of adventurous nature for which statistics and probability in form of astrology, numerology, and so on might have evolved although they could not become the exact sciences, even till today, for their involvement into endless calculations needed in their quasi-theories.
Pañcānga means five parts :
Tithi : The longitudes of the sun and the moon are measured from r (first point of Aries ) towards east along the ecliptic, and the difference of these longitudes determine the tithi, First tithi (pratipadā) lasts till the difference lies between 00 and 12°, the second tithi lasts till the difference lies between 120 and 240, and so on. In a lunar month, there are thirty tithis.
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