Purnima (also called Poornima, Pournima, Bangla: পূর্ণিমা, Sanskrit: पूर्णिमा (IAST: pūrṇimā)) is the Indian and Nepali word for Full Moon. The day of Purnima is the day (Tithi) in each month in which the full moon occurs, and marks the division in each month between the two lunar fortnights (Paksha). Full moon is seen when the sun and the moon are suppurated by 180 degrees. This lunar day is the considered auspicious for new beginnings. The Shukla (bright) Paksha is the fortnight before, and the Krishna (dark) Paksha is the fortnight after, Purnima. This moon phase lasts only for a while, when the sun , earth and the moon are aligned exactly in a straight line and this is called as Sun-earth-moon system. Full moon is considered as third among the four primary phases of the moon and the other three phases are new moon, first quarter moon and third quarter moon. The full moon causes 100% illumination, high tides, lunar eclipse.
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