Sandhya Puja is a unique ritual held at the conjunction of Ashtami and Navami Tithis during Durga Puja. In 2017, date of Sandhi Puja is between September 28 and September 29. The time in North India is at 9:36 PM on September 28. After usual rituals, the priest propitiates Goddess Chamunda.
The popular belief is that Goddess Chamunda killed Chanda and Munda at this period. Chanda and Munda were appointed by Mahisha to attack Goddess Durga. Goddess Chamunda appeared from the forehead of Goddess Durga and they killed Chanda and Munda.
The traditional ritual of Sandhi Puja consists of lighting 108 lamps. Flowers, leaves, clothes and jewelry are offered to Goddess Chamunda during the period.