How to calculate the exact Sahastra Chandra Darshan सहस्त्रचंद्रदर्शन date?

Recently we had the pleasure of celebrating the “Sahastra Chandra Darshan” सहस्त्रचंद्रदर्शन (SCD) of our uncle whom we lovingly call “Bhausaheb”. When 3M uploaded this image on Facebook, quite a few friends asked “How do you calculate the exact date for this ceremony?”. A Google search will tell you that it is celebrated sometime after a person's 80^th birthday… but that’s not really helpful!

First let us understand what SCD is all about! In ancient India, life expectancy of an individual was about 30 years. Hence anybody who crosses the age of 60 years was considered “Deerghayu” – person with longevity! So at each stage of life starting from the 60^th year, you have celebrations to cheer his/ her long life. One of these is SCD - a ceremony to celebrate the 1000^th full moon in a person’s life. Gautam Buddha is supposed to have lived up to his 1000^th full moon. Recently, this ceremony got publicity due to felicitations of Atal BihariVajpayee (2005), Satya Sai Baba (2008) & Lata Mangeshkar (2010)!

Calculating the exact date of a person’s SCD is now really easy thanks to good ol’ MS Excel. We know that a lunar month is made of 29.53 days. This means a person will complete 1000 months of his life in 29530 days. Let’s see how Bhausaheb’s SCD was calculated by 3M. On an MS Excel sheet type out the date “27-Dec-32” in a cell. In the cell right next to it type out “29530”. Add both these cells to get the date on which Bhausaheb completes 1000 months – “2-Nov-13”. Mind you, this is NOT the SCD date! Now refer any panchang like Date to find the Poornima (Full moon day) just before “2-Nov-13”. So the Sahastra Chandra Darshan in this case was on 17^th Oct 2013 which happened to be Kojagiri Poornima!