The Julian Calendar

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The Julian Calendar

• By Casey Gilbert

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What is the Julian Calendar

• Julian Calendar n the solar calendar
  introduced in Rome in 46 b.c. by Julius Caesar
  and slightly modified by Augustus, establishing
  the 12-month year of 365 days with each 4th year
  having 366 days and the months having 31 or 30
  days except for February.

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What is the Julian Calendar?

• Each day is numbered consecutively from January
  1, 45 BC.
• A way of syncing the calendar
• months and the seasons.

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Who developed the Julian Calendar?

• The Julian Calendar was originally developed by
  Julius Caesar and later modified by his nephew,
  Augustus Caesar.

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When and Where did the Julian Calendar Originate?

• The Julian Calendar system began in 46 BC and
  continued until 1582.
• The calendar was responsible for for time-keeping
  in Rome.

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Why was the Julian Calendar initiated?

• (Before the Julian Calendar) Political forces in
  Rome extended months to keep favored politicians
  in office.
• The government essentially controlled time in
  Rome.
• Julian Calendar helped to regain order and to end
  the abuse of time that was taking place in Rome.

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Why did we stop using the Julian Calendar?

• The tropical year of the Julian Calendar is
  approximately 365 ¼, causing an error of 1 day
  every 128 years
• Threw off method of calculating Easter.
• ( Average Julian year was slightly too long,
  causing Easter to fall a little earlier every
  year).

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What Calendar replaced the Julian Calendar?

• The Gregorian Calendar replaced
• the Julian Calendar in the 1500s.
• Greece and Russia used the Julian Calendar until
  the 1900s and the Orthodox Church in Russia
  still uses the Julian Calendar.
• Gregorian Calendar (The Christian Calendar) is
  based on the motion of the earth around the sun.
• We use the Gregorian Calendar today.

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How do we calculate Julian Calendar days?

•  a (14-month)/12   y year4800-a   m
  month 12a - 3
• JD day (153m2)/5 y365 y/4 - 32083
• Julian Date Converter!!!!

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Sources

• http//ukclipart.allinfo-about.co.uk/graphics/busi
  ness/cartoon_calendar.gif
• http//www.skeptics.com.au/journal/1995/1_calendar
  .htmJulian
• http//www.polysyllabic.com/Julian.html
• http//dictionary.reference.com/search?qjulian20
  calendar
• http//images.google.com/images?svnum10hlenqc
  artoonclockspell1
• http//webexhibits.org/calendars/calendar-christia
  n.htmlSECTION00310000000000000000
• http//www.riverbluffs.org/About20Us/Globe20-20
  Cartoon2026.gif
• http//wwwmacho.mcmaster.ca/JAVA/JD.html