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The Roman Julian Calendar

Page history last edited by PBworks 13 years, 2 months ago

The Roman Julian Calendar


Tom Heller



The Julian Calendar system was introduced by Julius Caesar in 46 B.C. This calendar was created primarily as a reform to the Republican Calendar. According to the Julian Calendar, a year consists of 365 days, and 366 every four years. This calendar was replaced by the Gregorian calendar today, but is still used in many Orthodox Churches.

Photo Credit: http://www.bible-history.com/archaeology/rome/julius-caesar-bust.html






The calendar was changed from the Roman Republican Calendar by Caesar because he was tired of its corruption. Priests back then would exploit the calendar for political reasons, and would add in days, sometimes months, in order to keep favored politicians in office.

The new calendar had an average of 365 ΒΌ days per year. So to solve this problem, Caesar created a leap year every four years, which meant that every four years, they would repeat February 23. In the Julian calendar, there was never a 29th of February. The year was broken into 12 months: Ianuarius, Februarius, Martius, Aprilis, Maius, Iunius, Quintilis, Sextilis, September, October, November, and December. In 44 B.C. the Romans renamed Quintilis, Iulius, after Julius Caesar, and in 8 B.C. Sextilis was renamed Augustus, after Caesar Augustus.

The major problem with the Julian Calendar was the fact that it was off by 11 minutes every year. The Julian system says a year is an average of 365.25 days, when it takes closer to 365.2422 days for the earth to return to the same point while orbiting the sun, putting the calendar off by 11 minutes, or 1 day every 128 years.


The Transition from Julian to Gregorian


Open the terminal and type in "cal 1752" and you will be shown a full calendar for the year 1752. (NOTE: This only works in Mac OS X). If you take a look at September, you will find that there are 11 days missing. it skips from the 2nd, strait to the 14th. This happens because in 1752, King George II officially changed the calendar of Great Britain from the Roman Julian to the Gregorian Calendar, which resulted in the loss of 11 whole days. Below is a short Flash video that displays this.




**Works Cited


Comments (2)

Anonymous said

at 12:59 pm on Oct 14, 2008

it doesn't seem to focus on the astronomy but it does have a video which makes it stand out from the rest.

Anonymous said

at 12:47 pm on Oct 14, 2008

I liked that you added a video in the webpage, it made it more unique. However, the page would be better if you added more pictures. You should also add some detail on the calendar and its astronomy, instead of focusing on how the calendar went wrong.

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