Pitr Paksha (Mahalaya Paksha)
The current Paksha is Pitr Paksha
(aka Mahalaya Paksha). This fortnight
is special for worshiping our Pitr (ancestors).
This is observed for about a fortnight starting
from the Purnima up to Amavasya Tithi
in the Chandramana month of
Bhadrapada / Aashvina. [+]
People perform tarpana every day and
Shraddha at least on one day during the
We have a daily worship of Devas - Deva Yagna.
Similarly, daily worship of Pitr is Pitr Yagna.
Then, there is a specific Tithi for
worship of specific Devas.
eg: Ashtami Tithi for Devi worship
Similarly there is a specific Tithi for
worship of Pitrs -
Amavasya (new moon) Tithi.
For both Deva & Pitr worship there
is the daily cycle and special
rites based on moon's cycle.
Likewise, both of them have an
annual cycle too.
For Devi worship, Navaratri is an
example of annual worship.
The equivalent for Pitr worship is
the Pitr Paksha.
I have been unable to locate any primary
source (Purana, Smriti) referring to
why this is being observed at this time.
It is said that this is the Paksha when
our Pitrs descend to our places.
If you have anymore information or
references, do let me know.
[+] See this for why variation in month.
Short answer: variation in defining
when a month starts.
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