Tharpanam means "That offering which satisfies". But what we mean by the word Tharpanam is the offering of water mixed with gingelly to the manes(dead ancestors).Though we have several ancestors, this offering is addressed to three generations of father, grand father and great grand father along with their wives in our family and maternal grand father, his father and grand father along with their wives in our mothers birth family. Only those whose father is dead are eligible to do Tharpanam. If maternal grand father is alive Tharpanam should not be done for his family but restricted to our family.

All the manes are supposed by our religion to live in the Pithru loka for some time and either be reborn as any being or go to lokas like deva loka, Vaikunta etc or even attain salvation by getting mixed with god. The pithru loka is populated by three group of pithru devas viz, Vasu, Rudra and Adhithya. These devas receive our oblations and make it reach to our manes wherever they are and in whichever form they are. The pithru loka is supposed to be on the unseen side of the moon. This portion gets exposed to sun on the new moon days. It is according to our concept lunch time for the people populating the pithru loka. These pithrus, since they have left the world are solely dependent on only their progeny to feed them. This feeding is done through Tharpanam. It is believed that if Tharpanam is not done out Pithru devas will curse us so that we may not have male descendents to offer tharpanam to us.

There are several type of tharpanams: -

Gunda tharpanam- the tharpanam which is done in the first ten days of death.

Brahma yagna tharpanam-This is the oblation supposed to be done daily to the devas, rishis and pithrus.

Parheni tharpanam- this is the tharpanam which is supposed to be done on the next day after annual sraddha .This at present is being done after sraddha on the same day , because the priest does not have time to come the next day. Here the tharpanam is offered only to ones pithru varga (paternal side)

The regular tharpanam which is supposed to be done on all amavasyas. Four Month beginnings viz mesha, karkidaga, thula and makara and eclipses.Our books have asked us to perform tharpanam on 96 days in a year but this is not being done nowadays.

Several acharyas have codified the method of tharpanam. Some of them are Apasthabha, Bodhayana, Drahyayana. What is given below is the manthras and method of the Apasthabha sutra.of Yajur veda. There is slight differences in the sankalpam among Iyers and Iyengars.Both versions are given here.It is understood that the tharpanam for rik vedis is almost similar but that for Sanma Vedis is different. There is also differences brought about by local practice and family tradition. People are advised to follow their traditions strictly. They have precedence over what is written down here. For example in many families tharpanam is done without wearing Vibhuti or Namam but there are certain families who do tharpanam wearing these. Some people do avahanams of Pithrus on two koorchas. Some on one koorcha and some on spread durbhas.

There are several rules regarding tharpanam though many of them are not being followed by most of the people.. They are:-

On the day of Tharpanam, till tharpanam is completed we are not supposed to drink/eat anything.
On the day of tharpanam, the daily rituals like Sandhya vandhana have to be first performed. Then before tharpanam one more bath has to be taken.

Wet cloth should not be worn during tharpanam nor is it right to wear cloth which was washed a day before and dried. The cloth has to be made wet the same day and dried. Pure white silk cloth can also be worn, but wearing this silk cloth you should not have eaten any food. If wet cloth is not dry, it should be seven times shaken dry in wind before wearing it.Except the tharpanam during eclipse all other tharpanams are to be done after 12 noon. Considering the difficulty, our law givers have agreed that it can be done after 8.30 AM.

As mentioned earlier nothing should be eaten or drunk before performance of Tharpanam.
Oblations should be done with hand full of water and not drops or spoon full of water.
The water should be poured out using the space between the thumb and the four fingers.

Every time a pinch of black til has to be taken. Care should be taken not to take it using the thumb and the index finger.
Pithru tharpanam should always be done with poonal hanging from the right shoulder to the left side of the body.
The pavithram for pithru tharpanam should be made out of three durbha and the koorcham should be made of 7 or 9 durbhas.
We should preferably sit on seat made of durbha(durbhasanam) while doing tharpanam and in its absence put few durbhas on the place we are going to sit,Silver vessels are prescribed for used during tharpanam. If not available copper vessels can be used. Under no circumstance should steel or other metal vessels are to be used.

Tharpanam should be done facing east or south. It is believed that it either should be done in our homes or in public holy places like shore of the river, sea active you happen to do it in the place belonging to some one else. We are supposed to compensate the owner of the property.

If Amavasya and the first of the month in which tharpanam has to be performed comes on the same day, then tharpanam for the sankramanam(first of the month) should be done.