Amavasya is the name of new moon night in Hindu religion. It is the first night of the first quarter of the lunar month. Since the moon is invisible on the day, Amavasya is also referred as no moon night. Amavasya is crucial day in Hinduism.
Many Hindus choose this day to make offering (tarpan) to the dead ancestors. The fortnight that starts with Amavasya is also referred as the Shukla paksha (bright half of the month). Mauni Amavasya in Hindu Magh month (January – February) and Mahalya Amvasya in Ashwayuja (September – October) are highly auspicious. Similarly the Amavasi in Aadi month is of great importance in Tamil Nadu. The Amavasya in Karkidakam month is of importance in Kerala.
In some regions people observe partial fast (Upvaas) or a complete fast on the day.
Amavasya is considered the ideal day to perform black magic and evil acts. Since there is no moon, Amavasya night is pitch dark and this provides the ideal setting to invoke evil powers.
Many astrologers advise against performing any important ceremony on the day as moon and important planets in Hindu astrology are not visible. In some regions, people do perform certain auspicious deeds on the day. But largely no new beginnings or important ceremonies are held on the day.Symbolically, the period from Amavasya to Purnima (full moon) is considered to be the gradual awakening and transcendence into the fullness. From darkness to the gradual realization of the Supreme Soul.