Dhanur Masa Pooja as the name implies is to be performed in the Hindu month of Dhanur Masa, December – January according to Gregorian calendar. This year (2017) it is from 16th December to 15th January 2018 (Makara Shankranthi).
During this month, festivals like Vaikunta Ekadashi, Datta Jayanthi are celebrated
The pooja / rituals during this month are performed before sunrise and this time is known as Sankramana Kala, which is very auspicious. Prepare Huggi / Ven Pongal or Sakkare Pongal for naivedya / blessed food.
People also visit temples before sunrise to offer prayers.