Friday, October 29, 2010

Indian Calendar - Panchang

Hello everyone,

The Diwali / Deepavali post last year:

seems to be bringing in truckloads of traffic to your blog. As I happened to glance at the calendar to count the days left for the festival of light, I got the inspiration for this post.

The calendar that we follow today is the Gregorian calendar, which was introduced in 1582. This was after it was found that the calendar in use till then, the Julius version, accounted for 365.25 days in a year, when in effect it was 365 days, 5 hours, 48 minutes and 46 seconds, thus slightly lesser than the assumed value. As a result, the equinox was moving steadily ahead in the year, and this was considered unacceptable.

As you know, in the current system, we have a leap year once every 4 years to compensate for the extra fraction of time taken by our beloved earth to revolve around the sun. In school, the unlucky individual whose birthday fell on 29th February was always urged to change his date of birth in order that he celebrate it ! The leap year problem is also an essential part of any quantitative aptitude test to ascertain the time period elapsed, etc.

Now, as the Gregorian calendar adds 1 day at the end of 4 years, it is not moving in synchronism with the sun. Spare the electrical jargon, but this is like a fixed step size, and does not vary smoothly taking into account the sun's variation.

Comparing the Gregorian with the Hindu calendar, generally referred to as the Panchang, we see that the Hindu version has a much more scientific relationship. While the former is based on the Solar variation and accounts for the earth's revolution around the sun as 12 months each having 30 days, the latter is based on the moon's revolution around the earth, where each month takes 28 days. To compensate for the loss of days, and extra month, called the Adhik Mas (mas is the word for month), is added every 30 months.

The Hindu counting of years generally concurs with the reign of a prominent king. For instance, the current year is the Vikram Samvat 2067, signifying that King Vikramaditya's reign started as many years ago (in 57 BC). There are many such Samvats known, but the Vikram Samvat is what is the most widely accepted and in use currently. The various months in the Vikram Samvat are listed below along with their approximate Gregorian Calendar counterparts:

Each of these months in the Hindu calendar (with 28 days) is subdivided into 2 cycles of moon waxing and waning. The 1st half is called the Krishna Paksha (dark period), where the moon wanes till Amavasya (new moon), and the Shukla Paksha (bright period), where the moon waxes till Purnima (full moon). This can be understood from the below image:

You can also check out my earlier post on the relevance of Ekadasi, the 11th tithi of the calendar:

The Hindu calendar in use is a combination of both solar and lunar inferences. The months are based on the moon, while the seasons are governed by the sun. A prominent example of a solar festival is that January 13-14 is celebrated as Pongal (in Tamil Nadu), Sankranti (north India) and Lohri (Punjab). All of these herald the entry of the sun into the Makar rashi, or the northward movement of the sun. Though the date is supposed to be somewhere between December 20th and 23rd, due to earth's tilt, it has kept sliding over years. Don't be surprised if in your future births, you find that Makar Sankranti is being celebrated in May, but that will take 1000s of years to come.

In fact, in certain temples, it is seen that on Sankranti day, sunlight graces the presiding deity. One of the temples that I can remember is the Sri Gavi Gangadhareshwara Temple in Bangalore, where the sunlight falls on the Shiva Lingam through Nandi's horns. Trust the ancients to establish the exact angle to honour God on the auspicious day !

Coming back to tithis, the days are calculated based on the actual longitudinal angular difference between the respective positions of the moon and the sun. Thus, it is common to see that the tithis vary in length, some shorter than our regular 24 hours, some extending beyond, and this leads to certain auspicious days being celebrated across 2 days of our Gregorian Calendar.

The Zodiac Signs or Rashis are another integral aspect of the Calendar, with 27 Nakshatras (Constellations) forming 12 Rashis, each of the latter accounting for 2.25 of the former. This is the basis of Indian Hindu Astrology, which again is a scientific art, and is very different from the general characterizations governing the Western Zodiac Date-of-birth based astrology. But more on that later, as it would requisite a separate post altogether...

For now, advanced wishes for a very Happy and Safe Diwali / Deepavali !

Nikhil Mundra

29th October 2010


Victory said...

I really appreciate you for these wonderful blogs. In fact I was looking for things that could help me in dealing with my colleague who is a born again Cristian, who continually approaches me to be a Cristian than a Hindu. Seems like I don't have to look every where but only your blog for my answers.. Thank you.

Nikhil Mundra said...

Hello Victory,

Thanks for your appreciative comment. Glad to know that you find my posts helpful.


sri said...

Good blog. But the month chaitra comes on march-april when a lunar calendar is used and on april-may when a solar or solar-lunar calendar is used. We, in india, generally use both these calendars according to our respective ancestors usage.