Bhishma Dwadashi is observed on the 12th day in the month of Magha (January – February) during the Shukla Paksha (waxing phase of moon). Bhishma Dwadashi 2023 date is February 2. The rituals is also known as Magh Shukla Dwadashi Tarpan and Shraddha. It is widely believed that Pandavas performed the last rites of Bhishma, the son of King Shantanu and Ganga
in Mahabharata, on this day.
Bhisma who was mortally wounded and was lying on a bed of arrows chose to leave the earth on the 58th day after the beginning of the Great War in Mahabharata. Bhishma was blessed with a boon that he can choose the day of his death. It is believed that he chose Magh Shukla Ashtami day to leave the earth and merge with Brahman.
On the Bhishma Dwadashi day, Pandavas performed the last rites of Bhishma Pitamah on the banks of Ganga
There is a popular belief that offering Tarpan and Shraddha on the day to ancestors is highly beneficial.
Some people also perform Tarpan in the name of Bhishma as he had no children.