Monday, February 27, 2012

The Julian Calender

The Julian Calender was established by Julius Caesar on 47 BC. It used a calculation of 365.25 days or 365 day and 6 hours. So therefore it was imperative that the fourth year has an additional day, on Feb 29th.

The First Month was Ianarius or January. The second month was Februarius, named after the Goddess Februa. The third month was Martis, named after Mars, which later on became March. The fourth was Aprilis, named after the goddess, April. The fifth month was Maius, after Mercury, which later on became May. The sixth month was Iona, or June, after the Goddess Juno. The seventh was Quintilis and the eighth, Sextils. Now the next month was September. Septa in Latin is Seventh and is equivalent to the Sanskrit Sapta. October is derived from Octa, meaning 8th, Ashta. November was Nova or Nava and December was Decem or 10th or Dasa !

In 1545, the seasons went haywire. The Equinoxes, Vernal and Autumnal, all came at the wrong dates. The Western astronomers were worried and they went to Pope Gregory to rectify the Julian Calender.

The error was obvious. When I first developed my software, there was error when one year = 365.25 days was used. The actual value, given by Sir Simon Newcombe is 365.256362424815. 12 decimals have to be used. Julian Calender erred as the decimals were only 2.

The Council of Trent authorised Christopher Clavius, who knew some Astronomy and Maths, to rectify this error. He had learnt Astro Maths from Pedro Nunes, a Jewish astronomer. Matteo Ricci was sent to India for this purpose, as the Indian Jyothish texts had the sine tables of Aryabhata, Madhava and Brahmagupta. No errors were reported in Indian calculations, which are sidereal and eternal.

Pope Gregory had to add 11 more days to the Julian Calender to rectify it ! This is the Western Calender ! Western Calender is based on the Tropical Zodiac and this Zodiac precedes one degree in 72 years. This Calender needs periodic adjustment. Whereas the Indian Astro Calender is based on the non moving Sidereal Zodiac.

It is surprising that Christopher Clavius, with Indian Knowledge, rectified the Julian Calender and now this Calender is known as the Gregorian Calender. He used six decimals !

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