Navami Shraddha could be performed for those souls who have departed on Navami Tithi.
Deceased may be died in any Paksha or Lunar Fortnights i.e. Shukla Paksha (Bright Fortnight) or Krishna Paksha (Dark Fortnight).
Navami Shraddha Tithi is also known as Matri Navami (मातृनवमी).
This Shraddha Tithi is most suitable day for performing Shraddha or last rituals of a mother by son.
Though it is significant for performing last rituals of mother it is also performed for other female members of the family.
It is believd that performing last rituals or Shraddha on Navami Tithi gives rest to the wandering souls.
When a soul gets last rites performed for it, it blesses the family.
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Navami Shraddha is also known as Naumi Shraddha and Avidhava Shraddha.
Pitri Paksha Shraddhas are Parvan Shraddhas(पार्वणश्राद्ध) and auspicious time to perform them is Kutup Muhurt and Rohina Muhurt.
Last rituals could be performed till Aparahna Kala (Post Meridian) gets over.
Tarpan (तर्पण) could be performed at the end of the Shraddha.
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