Amavasya (Hindi: अमावस्या, Malayalam: അമാവാസി, Tamil: அமாவாசை, Telugu: అమావాస్య, Gujarati: અમાવાસ્યા), also known as No Moon Day or New Moon Day, marks an important tithi in the Hindu Calendar. Of the 30 lunar phases (or tithis) that make up a lunar month in the Hindu calendar, Amavasya is the one when no moon is visible in the sky. Amavasya occurs once a month, with 12 such no moon days falling in a year. It also marks the beginning of Shukla Paksha, or the bright fortnight, of the lunar month.
Being the darkest day of the month, Amavaysa is considered one of the most powerful and impactful times of the year. This is why many important rituals and traditions are observed on this day by devotees across India.