Purnima and Amavasya: full and new Moon in the panchang
Purnima is the full Moon day, the fifteenth tithi of the bright fortnight. Amavasya is the new Moon day, the fifteenth tithi of the dark fortnight, or the thirtieth tithi.
What it is
At Purnima the Sun and Moon are about 180 degrees apart, and at Amavasya they are close together, in the same sign. These are the two points where the lunar month is divided into fortnights.
How it is worked out or read
The tithi that contains the full or new Moon is shown in the panchang, and the exact moment of full or new Moon is listed where the tithi ends.
Where it appears on this site
Both are in the panchang. The paksha article explains how the two fortnights are counted.
Full moon and new moon
Purnima is the full moon, the fifteenth tithi of the bright fortnight, and Amavasya is the new moon, the fifteenth tithi of the dark fortnight. The two are the turning points of the lunar month, and they mark the times when the Sun and Moon are opposite and close together in the sky.
Why these days matter in the calendar
Many festivals, fasts and observances are tied to purnima and amavasya, and the panchang marks them clearly. Because the lunar month begins and ends at these points in the amanta system, their dates also shape the calendar's organisation of months.
Observing the Moon
A reader can check purnima and amavasya by looking at the Moon. A full moon rises at sunset and is visible all night, while a new moon is hardly visible at all. Comparing the sky with the panchang is a simple way to confirm the count of tithis.
The full moon as an observed event
Seeing the full moon rise at sunset is a memorable experience, and many families mark purnima with prayer, fasting or simple gatherings. Because the full moon is so visible, it is one of the easiest calendar points to check against the sky. A reader who keeps track of the full moons across a year will see how they move through the seasons, rising earlier and later as the year passes.
The new moon is less visible, but its timing matters just as much for the lunar calendar. A reader who wishes to observe amavasya may check the day in the panchang and then note the sky over the following nights, when the Moon's thin crescent first appears.
Purnima and amavasya in the year's rhythm
Across the year, purnima and amavasya alternate about every fourteen or fifteen days, marking the two halves of each lunar month. Their regularity is a reason many traditions organise observances around them, and the rhythm they set is one of the clearest ways to see the lunar month's structure. A reader who plans a year can list both sets of dates together for a complete view.
Purnima in the tithi count
Purnima is the fifteenth tithi, and Amavasya is counted as the thirtieth. Each ends at the exact moment of full or new moon.