Aadi masam or Aadi month is the fourth month in traditional Tamil calendar followed in Tamil Nadu. Aadi Masam 2012 begins on July 17 and ends on August 17. Aadi masam in 2011 was from July 17 to 16th August. Aadi month begins on Karkadaka Sankranti or Karka Sankramana day when Sun transits to Karkataka Rashi or Cancer zodiac from Mithuna Rashi or Gemini zodiac. Aadi month in 2012 corresponds with Ashad maas and Shravan maas in North India Hindi calendars (Purnimant Panchangam) and other Amavasyant Panchanga systems – Marathi, Gujarati, Telugu and Kannada calendars.
Aadi Krithigai or Aadi Karthigai and Aadi Pooram are the major festival celebrated in Tamil month of Aadi in Tamil Nadu. Aadi Perukku, Aadi Amavasai, and Aadi Laksharchana are the auspicious rituals observed in Palani temple during Aadi masam. Next month in Tamil calendar is Avani month.
Read here about the significance, importance, fears, myths, doubts about Aadi masam.