Avani Avittam is the Tamil name for Upakarma, the annual renewal of the sacred thread (poonool/yajnopavita) and of Vedic study, observed chiefly on the Shravana Purnima full moon in the Tamil month of Avani (August–September). Men and boys who wear the sacred thread replace it with a new one after rites of atonement, and the following day is devoted to Gayatri Japam.
When: Shravana Purnima and adjacent days in the Tamil month of Avani (August–September); Gayatri Japam follows the next day
Where: Tamil Nadu — observed at home, on riverbanks and at temple tanks; kept by Tamil communities worldwide
Observance: Kamokarshit japam (atonement), tarpanam to rishis, replacement of the sacred thread, resolve to renew Vedic study
By Veda: Yajur Upakarma on Shravana Purnima · Rig Upakarma on Shravana nakshatra day · Sama Upakarma on Hastha, in Bhadrapada
Regional name: Avani Avittam (Tamil) · Upakarma / Upakarmam · Shravani (North India) — same day as Raksha Bandhan's full moon
Renewing the thread and the study
Upakarma means 'beginning': in the Vedic scheme of the year, the bright fortnight of Shravana marked the reopening of Vedic study after the monsoon, and the rite has been kept annually ever since. In Tamil Nadu the day takes its name from the month of Avani and the Avittam (Dhanishtha) nakshatra associated with the season's full moon. Those who have received the upanayana samskara — the investiture with the sacred thread — gather to perform kamokarshit japam, a formal act of atonement for lapses in discipline over the past year, followed by tarpanam honouring the rishis through whom the Vedas descend, each family invoking the seers of its own lineage and shakha. The old yajnopavita is then replaced with a new one to Vedic mantras. The rite is thus less about the thread itself than about beginning again: cleansed of the year's shortcomings, the student takes up the Veda anew.
How the day is observed
Followers of the Yajur Veda — the majority in Tamil Nadu — perform upakarma on Shravana Purnima; Rig Vedis observe it on the day of Shravana nakshatra, and Sama Vedis later, on Hastha nakshatra in the following month, so the family's shakha determines the exact day. On the morning itself, men and boys bathe, ideally in a river or temple tank, and sit in groups led by a vadhyar (priest) who conducts the sankalpam, the atonement japam, the rishi tarpanam and the donning of the new thread, the old one being reverently discarded. New students may receive their first upanayana in this season. At home the day is festive: an oil bath, new clothes, and a special meal in which vadai and payasam usually appear. The next morning is Gayatri Japam, when the Gayatri mantra is repeated — traditionally 1,008 times — as the concentrated resumption of daily sandhyavandana discipline.
Keeping Avani Avittam in Ottawa & Canada
Avani Avittam is a household rite and travels completely. Tamil families in Ottawa keep it at home or in small groups: obtain new sacred threads in advance (Indian grocers and temple stalls usually stock them in the season, or bring a supply from India), and follow the sankalpam and mantras with a local priest, an online vadhyar session streamed from India, or a printed upakarma manual for your Veda and shakha. Mind the time difference — Indian live sessions land in the very early Ottawa morning, so many families instead perform the rite at a suitable morning hour in Eastern Time on the correct tithi as computed for their locality; this site's panchang pages give Ottawa timings. An oil bath, new clothes and a festive lunch complete the day, and Gayatri Japam follows the next morning. Check your local temple for group upakarma arrangements.
Questions
Who observes Avani Avittam?
Those who wear the yajnopavita, the sacred thread received at upanayana — traditionally men and boys of the communities that maintain Vedic study. Households observe it together, with the women of the family preparing the festive meal and the whole family sharing the day.
Why do different families observe upakarma on different days?
The day depends on the Veda a family follows. Yajur Vedis observe Shravana Purnima, Rig Vedis the day of Shravana nakshatra, and Sama Vedis perform upakarma on Hastha nakshatra about a fortnight later. All three renew the thread and the commitment to study.
What is Gayatri Japam and why is it the next day?
Gayatri Japam is the repetition of the Gayatri mantra — traditionally 1,008 times — performed on the morning after upakarma. Having renewed the thread and atoned for the year's lapses, the observer re-consecrates the daily discipline of sandhyavandana, of which the Gayatri is the heart.
Is Avani Avittam the same day as Raksha Bandhan?
They share the Shravana Purnima full moon in most years. Raksha Bandhan is the northern festival of the rakhi tied between sister and brother; Avani Avittam is the southern upakarma rite. The two observances are distinct but often fall on the same day.
Source: Vedic upakarma tradition as kept in Tamil Nadu households. Regional versions may vary — this text follows the version most widely used in community worship.