21 January 2016 is Pradosh Vrat. As it falls on Thursday, it is also observed as Brihaspati Pradosham or Guru Pradosha Vrata.
It falls on Trayodasi in Shukla Paksha in Paush Month (Pushya Masam) in Hindu calendars followed in North India as well as Amavasyant calendars.
It falls in Makaram Month in Malayalam calendar, Thai Masam in Tamil Panchangam and Maagh Month in Bengali Panji.
Guru Graha Shanti Puja / Brihaspati Dosha Nivarana Homam is performed by some devotees on Brihaspati Pradosh Vrat.
This Pradosh is even more auspicious as it falls during Ardh Kumbh Mela of Haridwar.
Pradosh Puja time is 4.30 to 6’0 clock in the evening. Pradosha Astakam is an auspicious prayer chanted during Pradosh Shiv Pujan.