Introduction

Do you know the Definition of Year is different in different calendar system? While, the concept of ‘Year’ is central to all calendar systems, including Indian Calendar System and  Wester Calendar System. The way to measuring the year’s duration is different in different calendar systems. 

Where in the Western calendar system, the measurement of years’ duration is based on a solar-based system, in the Indian Calendar System, it is based on the integration of lunar phases with solar cycles. In this article, the different measurements of each calendar system are explained briefly. It will give you the knowledge on how ‘Year’ is calculated according to different systems, why leap year or Adhik Maas occurs, what the zodiac roles are in calculating the year, etc. 

What Is An Year?

A Year is a time-measuring unit, taken by the Earth to revolve around the Sun. It contains a fixed or variable number of days, ranging from 350 to 360 days, depending upon the calendar system used for its measurement. ‘Gregorian Calendar System’ is the common and most widely used measuring system for the year that counts about 365.2425 days in a year. While, other calendar systems, such as the Hindu or Indian Calendar System, count up to 354 to 365.25636 days in a year. 

Definition Of Year In Western Calendar System

In the Western Calendar System, the Year is defined as the sum of days of all 12 months adding up to 365 or 366 days in a full year. It is measured using the Gregorian calendar, which is a solar-based system of measuring days, months, and years. Here are the following characteristics of Western Calendar System for measuring the year:

Solar Year

The Gregorian calendar uses a solar year of 365.24 days. This period is fixed, and every four years, the leap day is added in February to keep the calendar aligned with the Earth’s orbit. 

The Gregorian calendar is the most commonly used calendar in the world today. It defines a solar year as 365 days and adds a leap day (February 29) every four years to account for the extra 0.24 days.

Leap Year

• Every four years, an additional day is added to the calendar in the form of February 29 to adjust for the fractional day (0.24 days) in the solar year. This is known as a leap year. 
• This results in a year being either 365 days in a common year or 366 days in a leap year.
• A leap year has 366 days, while a normal year has 365 days.

Definition Of Year In the Indian Calendar System

In the Hindu Calendar System or the Indian Calendar System, a ‘Year’ is defined as the sum of days of months, accumulating the solar as well as lunar cycle systems. Therefore, the number of days varies in the year according to the Hindu Calendar System. 

In the Solar Year system where it contains 365.24 days in the Lunar Year system it is  354.36 days. Hence, a difference of 11 days occurs between the two system which is adjusted in the form of ‘Adhik Maas’ or ‘Mal Maas’. 

Solar Year

The solar year in the Indian system is called Saur Maas and is similar to the Western solar year, lasting 365.24 days. The difference is in the name of months whose counting starts from Chaitra instead of January, which falls in the month of February or March, depending upon the calculation. Each Hindu month spans over 30 days, calculated by following the Sun’s movement across the zodiac, each month. 

Zodiac

The 12 zodiac signs (Rāśis) along the elliptical path of the Sun are the twelve divisions of the sky that the Sun appears to pass through over the course of a year. Each part or division is associated with a constellation, which gives the zodiac sign its specific name. Here are the 12 zodiac signs covering 30 degrees of total path angle (360 degrees). The Sun spends about 30 days in each zodiac, making it 12 Sankranti events in a year.

Lunar Year 

Lunar Year in Hindu Calendar System are based on the moon’s cycle from full moon to full moon (Purnimanta system of North India) or New moon to new moon (Amanta System of South India). Each lunar month being about 29.5 days, hence it accumulates to 354.36 days in a complete lunar year of 12 lunar months. Here are the list of 12 lunar months according to Hindu Calendar system.

Adhik Maas

Unlike the Western calendar system, which is based on the solar year, the Hindu Calendar System is based on the luni-solar system, which is a blend of both the solar and lunar systems. In the Luni-solar system –

• Months are counted according to the moon’s cycle or phases.
• The year is counted according to its transition in the Zodiac. 

Hence, when both systems are synchronized, an extra month emerges which is adjusted in the form of Adhik Maas every 2.5 – 3 years.  Here is the calculation –

• 1 Lunar Month = 29.5 days = 29.5 * 12 = 354 days in one lunar year
• 1 Solar Year = 365.24 days
• Difference = 365.24 – 354 = 11 days (between one solar year and to lunar year)
• Hence, each year there is a gap of 11 days, which adds up to 30 – 33 days in 2.5 – 3 years = (11* 2.5 or 3) = One Extra Month.
• This extra month occurs every 2.5 or 3 years, which is known as ‘Adhik Maas’, ‘Mal Maas’ or ‘Purushottam Maas’. 
• In the circumstances when ‘Adhik Maas’ occurs the Month’s name repeat in that year such as Adhik Chaitra then Chaitra, or Adhik Baisakh then Baisakh. 
• Any kind of auspicious work in the ‘Adhik Maas’ is prohibited in the ‘Adhik Maas’ or ‘Mal Maas’. 

Note: Here, we produced rough estimation of the number of days in ‘Adhik Maas’ while, the exact number  of days in ‘Adhik Maas’ can be calculated with the help of ‘Panchang’ or Astronomical calculations of that specific year. 

Saur Sankranti

Saur Sanskranti is the phase when the Sun transits from one Zodiac to another Zodiac. The Sun remains for 30 days in one Zodiac, and when the duration is over, it transits from the current one to the next one. This transition is referred to as ‘Saur Sankranti’ and therefore there occur 12 Sankranti for each 12 Zodiacs. Below is the simple calculation to understand the science behind Sankranti:

• Sun’s Eliptical Path = 360 Degrees
• The Path is divided into 12 Divisions = 360/12 = 30 Degrees = Area of Each Zodiac
• The Sun covers about 1 Degree each Day = 1 * 30 = 30 Days
• Hence, the sun remains for about 30 Days in one Zodiac.
• Hence, there are a total of 12 transitions of the Sun = 12 Saur Sanskranti = One Solar Year or Saur Varsh

The names of the 12 Sanskranti are as mentioned in the table below: 

Conditions for Adhik Maas

Now, as you understood the concept of Adhik Maas in the Indian Calendar System, it is necessary to know the conditions for Adhik Maas. The ‘Adhik Maas’ occurs every 2.5 to 3 Years, but when and in which month? To understand this, understand the following key conditions:

• The first and foremost condition for Adhik Maas is that the Sun should not make any transit during a lunar month. 
• Hence, that Lunar Month in which the Sun does not transit from one zodiac to another, that month becomes ‘Adhik Maas’ or ‘Mal Maas’. 
• Here you must note that in all these calculations Solar year and Lunar year are going parallely. Hence, every 2.5 – 3 year the Sun ’s transition in a specific lunar month goes absent due to 11 days gap each year. 
• Thus, the month in which sun’s transition absent that month declared as ‘Adhik Maas’.
• Take for example the Sun does not make any transition in ‘Shravan Month’ of an specific year then that month becomes ‘Adhik Maas’ and named as ‘Adhik Shravan’. 
• The same is applicable for each lunar month when it becomes ‘Adhik Maas’. 

Indian Calendar System V/S Western Calendar System: The Difference

Conclusion

In conclusion, the definition of year in both the Indian and Western calendar systems is centred around the Earth’s orbit around the Sun.  However, their approach to measuring time, adjusting for discrepancies, and structuring the year varies. Both calendar systems are praiseworthy for their uniqueness and distinct characteristics. Where the Western Calendar System is straightforward and practical, the Hindu calendar system is a bit closer to nature and the astronomical behaviour of planets and cosmic bodies. 

Frequently Asked Questions (FAQs)