Ekadasi, panchangam questions

From the Bhakti List Archives

• February 5, 1999


Dear Bhaktas,

I hope there are one or two panchangam experts
among us who can answer the following questions.

I am a little confused about when to observe
Ekadasi, Dvadasi, and tirunakshatrams in the 
U.S., or for that matter, any time zone different
from India.  

The problem is this: the panchangams we get are 
printed according to Indian time.  The panchangams
provide, for a given day:

    a) sunrise and sunset times, useful for doing
       sandhyAvandanam at the appropriate times
    b) tithi (phase of the moon)
    c) nakshatram (the constellation that is in
                   ascendance)

I can recalculate (a), the sunrise and sunset times,
very easily. This Web site is very useful for this:

  http://aa.usno.navy.mil/AA/data/

However, I am confused about (b) and (c).  The
phase of the moon should be the same at any given
time anywhere in the world.  For example, if it 
is paurNami (full moon) in India at 8 AM, it is also
paurNami in San Francisco at 7:30 PM (previous date),
since San Francisco is 12.5 hours behind India time.

My questions are as follows:

  1) Does this mean that if Ekadasi ends in the morning
     according to the Indian panchangam, in the U.S.,
     we should observe Ekadasi the date before? What is
     a general principle to follow to account for the
     time difference?
 
  2) What is the definition of Ekadasi for Sri Vaishnavas?
     Is it the percentage of moon illuminated, or number of
     days in a paksha? 
     I know it is different from smArtas, but in what way?

  3) Do nakshatras follow the same rule as the tithi?
     I.e., should we observe functions a day earlier in 
     the U.S., accounting for the time difference?

  4) Does sunrise/sunset have anything to do with reckoning
     on day as Dasami and another as Ekadasi, for example?

I look forward to your responses.

Thanks,
Mani