Nepal's Mata Tirtha Aunsi falls on which lunar phase?

Nepal’s Mata Tirtha Aunsi falls on Amavasya, the new-moon phase.

The festival is also called Matatirtha Aunsi or Aama ko Mukh Herne Din, meaning “the day to see one’s mother’s face.” It occurs on the new moon of the lunar month of Baisakh, corresponding roughly to April or May in the Gregorian calendar.

Mata Tirtha, a pilgrimage site near Kathmandu, is central to the observance. People honor living mothers with sweets, clothing, and gifts, while others visit Mata Tirtha Pond to remember mothers who have died. A traditional belief says that a deceased mother’s face may appear in the pond to a devoted child.

The name can cause confusion because “Aunsi” is sometimes treated simply as a festival name rather than a lunar-phase clue. It specifically denotes the new moon, so Purnima—the full moon—is the opposite phase, while Pratipada is the first day after the new moon and Ekadashi is the eleventh lunar day.