Four ways of estimating Time

A small post.

Jyotish is a way of calculating ‘change’. most commonly this change is estimated with respect to Time, or Kaal. We try to determine how things will change with Time. ie we try to determine the role of Kaal in determining the direction of our existence. How we change with ‘Time’.

Kaal काल in Sanskrit (Devbhasha Samskrutam) has a several meanings ie fate, destiny, body of time, black, attribute-less, tenses of grammar, era, iron, perfume, time of death, time of annihilation, end, part, section, prosody, measure of time, fixed point, pupil of the eye, names of some trees etc.

Simply put, the ‘change’ in our lives is broadly understood as Kaal. It is not a fixed thing and is always relative to something else. Time is the change that we sense in one thing when we compare it to another thing, ie it is basically a measure of ‘change’. We study how things change, how to quantify this change and the quality of this change. 


We understand a ‘year’ to be 365 days and a leap year every 4th year. But in Jyotish, as per the Surya Siddhant there are 4 broad categories of years or varsh. We humans have 4 ways of measuring one ‘day’. Thus there are 4 types of ‘months’ and 4 types of ‘years’ that we use. 

  1. Saura – One Saura day is the time that the Sun take to change his position from one degree to the next. ie the time take to traverse one degree of the zodiac. 30 saura days make up one saura month, ie the time taken by the Sun to cover 30deg of a rashi.
    Saura calculations are used for things related to the Sun in astronomical terms, Solstices, equinoxes, sankrati-s, times of eclipses etc.
  2. Savana – One Savana day is the time interval from one sunrise to the next sunrise. ie the time taken for the Sun to be successively visible at the eastern horizon. This duration can vary depending on the latitude of the place in question, the season etc. This is the commonly used system at the current times in routine civil life.
  3. Nakshatra – In this system, one day is the time taken by the Moon to traverse one Nakshatra. Here one ‘nakshatra month’ is the time he takes to traverse all 27 Nakshatra. 12 such months make a Nakshatra year.
  4. Chandra – In this system, a day is called a Tithi and this is calculated based on the difference of degrees between the Sun and the Moon in the skies.
    1 Tithi is the time interval which is equivalent to a distance of 12 deg between the Sun and the Moon as seen from the Earth. 1 tithi is shorter than one saura day by 1/60.
    A Chandra Maas (lunar month) begins from the Shukla Pratipada (first day of bright fortnight) and ends on the Amavasya (ie no moon day or the last day of the dark fortnight). Thus the tithi-s repeat every 29.5 days.

We use the 4 types of years, Saura, Savana, Nakshatra and Chandra even now. Regular people stick to the savana ie civil calender, but Brahmins and people who perform typical pujas will use the other systems too. These 4 systems are continually corrected so that they match up every 5 Saura years. This is called the 5-year Yug cycle. And we call it the Luni-solar year.

Jyotish is highly complex and we must be proud of our heritage. But as most of it is lost we have to make attempts to research and relearn by studying what we can. Starting to learn Sanskrit, ie our real mother tongue would be a good beginning. So that we can at least read what our original books are actually saying. Understanding those would be the next step.