Navratra 2015: Why fasts overlap during the fasting season decoded!

Today is the 6^th day of Navratra, wait no it is the seventh day! Why, it is so perplexing? If you are also confused in the counting of Navratra days, here we are to help you.

The holy days of Navratra began on October 13 and will continue till October 21.

This means that on October 20, one should be celebrating the 8^th day of auspicious festival but wait here is a twist.

The 8^th day or as it is called Ashtami will be celebrated on October 21 i.e. Wednesday with Navmi across India.

If you are still confused why the fasts overlap then there is a scientific reason for it:

• The Hindu calendar is a lunar calendar, which means its days are based on the movement of the moon unlike a Gregorian/solar day which has 24 hours.
• The lunar calendar dates never change, because the rotation of the earth about its axis is at a uniform rotation speed (15 degrees per hour).
• One lunar day is the time taken when there is a 12 degree change in the angle subtended by sun (S) and the moon (M) on the earth (E), i.e. ∠SEM.
• So, this means the length of a tithi (date) would have been the same.
• At every turn of the tithi, the earth is at a new position with respect to the sun, as the earth has also been rotating and revolving all the time!
• All these complexities mean that the length of the lunar day (tithi) is not constant, and can vary somewhere between around 19 hours to 26 hours. 
• So, if a tithi begins after sunrise on a certain solar date and ends before sunrise on the next date, it is not shown on calendars, and you think that a day is missing. 

And, this is your answer. The missing day which means an extended fast during Navratri.