Why the difference between Western and Hindu Calendar

Story:

There is lot of difference between the Western calendar and Indian calendar, in calculating the days, months and years, and also the names of months. While September, October, November and December should the the 7th, 8th, 9th and 10th months of the year respectively according to the Roman calendar, it is not the same in western calendar. And these months hold right in the Hindu-Telugu calendar.

Analysis:

The origin of Roman Calendar

The Roman calendar is claimed to be developed by Romulus, the one who found Rome around 753 BC. His version of calender had ten months.
Martius (31 days)
Aprilis (30 days)
Maius (31 days)
Iunius (30 days)
Quintilis (31 days)
Sextilis (30 days)
September (30 days)
October (31 days)
November (30 days)
December (30 days)

This calendar system constituted only 304 days in a year. The extra winter days that came between the end of December and the beginning of the following March, were not assigned to any month in this sytem. The following months were named depending on their position in the calender. Month of Quintilis comes from the word quinque that means five, Sextilis from sex meaning six, September from septem meaning seven, October from octo meaning eight, November from novem meaning nine and December from decem meaning ten.

In 713 BC, Numa Pompilius, the second traditional king of Rome made some changes to the Romulus Calendar by adding the months of January and February before the beginning of the original ten months. As a result of this, the names of Quintilis, Sextilis, September, October, November and December that imply fifth through tenth months of the year did not agree with their position in the calendar.

The Western Calendar (Gregorian)

The Gregorian calendar is the internationally accepted civil calendar, which is commonly referred to as Western or Christian calendar. The Western calendar is a result of several reforms of the Julian calendar system, which is again a reform of the Roman calender, which also made reforms to the lunar cycle. The western calendar is a solar calendar that considers days as the basic unit of time, and groups them into 12 months that form a year containing 365 or 366 days. You can read further information in the reference section. However, there is a difference between this Western calendar and the Indian-Hindu calendar.

The origin of Hindu Calendar

The Indian national calendar is the official calender used in India. It is referred to as Saka calendar, and more commonly called the Hindu calendar. It 1957, the Calendar Reform Committee developed this lunisolar calendar in which months are named after traditional Indian months shown in the table below. This reformed Hindu calendar began in the Saka Era, Chaitra 1, 1879, which actually corresponds to March 22, 1957.

* In leap years, Chaitra has 31 days, starting on March 21 instead. Note that September, October, November and December agree with their position in this calendar.

The new year in Hindu system is called by various names Yugadi, Ugadi or Samvatsradi in Deccan region of India (Telugu calendar), Gudi Padwa by Marathis, Thapna by Marwaris, Cheti Chand by Sindhis, Sajibu Cheiraoba by Manipuris, Baisakhi in Punjab and Puthandu in Tamil Nadu. Rest of north India celebrate it in the name of Chaitra navaratri.

The Telugu new year name Yugadi or Ugadi is derived from the word “Yuga Adi”, meaning ‘the beginning of a new age’. The Telugu new year falls on a different day every year as the Hindu calendar is based on lunisolar system. The lunisolar calendar system calculates date depending on the moon phase and also the time of solar year. So, if it is a tropical solar year, then the lunisolar calendar will indicate the season.

The Hindu-Telugu calendar begins with the month of Chaitra that comes between March and April, where Ugadi marks the first day of the new year and is celebrated as a festival. This Hindu-Telugu calendar is also called the panchang, panchanga or Panjika, and is an important aspect of traditional hindu life because it calculates all the important dates of festivals, and decides auspicious times for important rituals. Most of the festivals in Hindu calendar are only calculated on the lunar movements.

A lunar year of Hindu calendar consists of 12 months. One lunar month comprises of two fortnights, which begin with the new moon called amavasya and ends with full moon night called purnima. The lunar days are referred to as tithis. Every month has 30 tithis, that vary from 20 – 27 hours. Mentioned below are the 15 moon days of the Hindu month.

Prathama – First
Dvitiya – Second
Trtiya – Third
Chaturthi – Fourth
Panchami – Fifth
Sasthi – Sixth
Saptami – Seventh
Astami – Eighth
Navami – Ninth
Dasami – Tenth
Ekadasi – Eleventh
Dvadasi – Twelfth
Trayodasi – Thirteenth
Chaturdasi – Fourteenth
Panchadasi – Fifteenth

Purnima – Suklapaksha – Full Moon
Amavasya – Krsnapaksa – New Moon

Therefore, the western calendar is solar based, and Indian-Hindu calendar Lunisolar, which accounts to the difference between them.

References:

Roman Calendar
Julian Calendar
Gregorian Calendar
Ugadi
Lunisolar Calendar
Saka Calendar