12 October 2015 is Somvati Amavasya. As it falls on Monday, it is observed as Somavati Amavasya (Ama Somavar Vrata). This No Moon is also referred to as Mahalaya Amavasya or Sarva Pithru Amavasya.
Amavasya of October 2015 falls on Ashwin Month as per North Indian Hindi calendars. It coincides with Bhadrapada Month Amavasya as per Marathi, Gujarati, Telugu & Kannada calendars.
It is Purattasi Amavasai in Tamil calendar, Kanni Month Amavasya in Malayalam calendar and Ashin Amabasya as per Bengali calendar.
Performing pitru tharpan, pinda daan, arghya, punya snan, etc.. are considered highly meritorious on the occasion of Somavati Amavasya.
This Amavasya marks the end of Bhadrapada Month in Amavasyant Panchangams.