The word Ugadi derives from the word Yugadi. 'Yuga' is the word for 'epoch' or 'era', and 'aadi' stands for 'the beginning'. Yugadi specifically refers to the start of the age we are living in now, Kali Yuga. Kali Yuga started the moment when Lord Krishna passed away. Maharshi Vedavyasa describes this event with the words 'Yesmin Krishno divamvyataha, Tasmat eeva pratipannam Kaliyugam'. Some Indian historians date the beginning of Kali Yuga to 3102 BC.
The festival marks the new year day for people between Vindhyas and Kaveri river who follow the southern Indian lunar calendar, pervasively adhered to in the states of Andhra Pradesh,Karnataka and Maharashtra. This calendar reckons dates based on the Salivahana era (Salivahana Saka), which begins its count from the supposed date of the founding of the Empire by the legendary hero Shalivahana. The Satavahana king Shalivahana (also identified as Gautamiputra Satakarni) is credited with the initiation of this era known as Shalivahana. The Salivahana era begins its count of years from the year corresponding to 78 AD of the Gregorian calendar. Thus, the year 2000 AD corresponds to the year 1922 of the Salivahana Era.
In the terminology used by this lunar calendar (also each year is identified as per Hindu Calendar), Yugadi falls on Chaitra Shudhdha Paadyami or the first day of the bright half of the Hindu month of Chaitra. This generally falls in the months of March or April of the Gregorian calendar. In 2009, Yugadi falls on March 27th.
Telugu calendars have a sixty year cycle and starts the new year on ugadi i.e., on Chaitra Sudhdha Paadyami. After the completion of sixty years, the calendar starts anew with the first year.
Ugadi (start of new year) is based on Bhāskara II lunar calculations in 12th century. It starts on the first new moon after Sun crosses equator from south to north on Spring Equinox. For example, the time for the new moon for Bijapur where Bhaskaracharya was born can be determined from the website [1] However, people celebrate Ugadi on the next morning as Hindu day starts from sun rise.
