To determine in which constellation the Sun is found at any time of the year.
Explanation:
Have located the stars in the various constellation. The Sun is found at any time in the year.
Based on this the birth dates are determined for its meaning. But any year or every year the sun is found in the same place and same time.
The various constellation connected to sun and earth are Sagittarius, Capricorn, Taurus, Gemini, Cancer, Aquarius, Pisces, Virgo, Libra and Scorpio, Aries.
The constellation and date numbers are defined with appropriate meaning.
For example, the Sun is found to be in Virgo from September 16 to October 31.
