sankranthi (Pongal) is the only festival of Hindu that follows a solar calendar and is celebrated on the fourteenth of January every year. sankranthi named also Pongal.sankranthi  has astronomical significance: it marks the beginning of Uttarayana, the Sun's movement northward for a six month period. In Hinduism, Uttarayana is considered auspicious, as opposed to Dakshinaayana, or the southern movement of the sun. All important events are scheduled during this period. Makara Sankranthi refers to the event of the Sun entering the zodiac sign of Makara or Capricorn.

sankranthi signals the end of the traditional farming season. Farmers perform puja to some crops,the end of the traditional farming season. It also sets the pace for a series of festivals to follow in a calendar year.Bogi' is celebrated on January 13, 'Pongal' on Jan 14, 'Maattuppongal' on Jan 15.

 the first day, Bhogi, the old clothes and materials are thrown away and fired, marking the beginning of a new life. The second day, the Pongal day, is celebrated by boiling fresh milk early in the morning and allowing it to boil over the vessel - a tradition that is the literal translation for Pongal. People also prepare savories and sweets, visit each other's homes, and exchange greetings. The third day, Mattu Pongal, is meant to offer thanks to the cows and buffaloes, as they are used to plough the lands.
Pelli Pata ( Bit )-2
Thus, the harvest festival of Pongal symbolizes the veneration of the first fruit. The crop is harvested only after a certain time of the year, and cutting the crop before that time is strictly prohibited. Even though Pongal was originally a festival for the farming community, today it is celebrated by all. In south India, all three days of Pongal are considered important. However, those south Indians who have settled in the north usually celebrate only the second day. Coinciding with Makara Sankranti and Lohri of the north, it is also called Pongal Sankranti.The Gift

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