Observance
Amāvāsyā and Pūrṇimā — the two ends of the month
अमावास्या · पूर्णिमा
In short
Amāvāsyā is the new moon, the moment the Moon catches up with the Sun and the lunar month ends. Pūrṇimā is the full moon, when the two are opposite. They are the fifteenth tithi of each fortnight, and between them they frame every lunar month.
Why it matters They are kept very differently: Amāvāsyā is traditionally associated with remembrance of ancestors, and Pūrṇimā with observances and offerings of a different character.
Take away One month ends and another begins in the dark, not in the light.
The astronomy
The Moon gains about twelve degrees a day on the Sun. When the gap closes to zero, that is Amāvāsyā; when it reaches a hundred and eighty degrees, that is Pūrṇimā. Each is a tithi like any other — a span of time, not an instant, though the exact conjunction and opposition are instants inside it.
A day is called Amāvāsyā or Pūrṇimā if that tithi is running at its sunrise.
Amāvāsyā and remembrance
The new-moon day is widely kept for the ancestors — for tarpaṇa and śrāddha observances — rather than for beginning new undertakings. That is the reason this site’s day-quality reference marks Amāvāsyā as a day traditionally set aside for those observances rather than for new work.
Sri Kumar Gurukkal performs ancestral remembrance rites — śrāddha, tarpaṇam and the Pitṛ Pakṣa observances. He does not perform funeral rites: antyeṣṭi, cremation or last rites. That distinction is stated on this site wherever the ceremonies are listed, because a family arranging things at a bereavement should not have to discover it at the wrong moment.
Pūrṇimā
The full-moon day carries a number of observances through the year, several of which are named for the lunar month they fall in. Satyanārāyaṇa Pūjā is commonly performed on Pūrṇimā, though it is not restricted to it.
Where a household keeps a monthly Pūrṇimā observance, the date follows the tithi and therefore moves through the English calendar. This site’s calendar lists them for the Bay Area.
What a family may do
- If your family keeps a monthly tarpaṇam, the Amāvāsyā dates are in this site’s calendar and in the subscribable feed.
- For an annual śrāddha, the date is fixed by the tithi rather than the English date, and it is worth confirming with Gurukkal each year.
- For a Satyanārāyaṇa Pūjā at home, a Pūrṇimā is a common choice but not the only one — ask about a date that suits the household.
Often misunderstood
- That Amāvāsyā is an inauspicious day. The traditional reading is narrower: it is kept for particular observances rather than for beginning new undertakings.
- That the new moon is a single instant. The conjunction is; the tithi is a span of about a day around it.
Where traditions differ
- Amānta traditions end the lunar month at Amāvāsyā and pūrṇimānta traditions at Pūrṇimā, so the same tithi can belong to differently-named months in two households. The observances are the same; the month name is not.
Explaining it to a child
When the Moon disappears completely, one lunar month has finished. When it is completely round and bright, we are halfway through. Families keep different kinds of days at those two moments.
Sources and review status
This page describes widely-documented traditional practice, prepared from the sources listed below. It is not a ruling, and it does not describe Sri Kumar Gurukkal’s personal practice unless it says so explicitly. Family-specific guidance should be confirmed with him.
- SaivaPriest — festivals and observances through the year
- SaivaPriest — Satyanārāyaṇa Pūjā
- SaivaPriest — what Gurukkal performs, and what he does not
Read next
Family-specific guidance — what your own tradition asks for, and what suits your household — is a conversation with Gurukkal, not a page on a website.