February- The Multifaceted Month!

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February- The Multifaceted Month!

• February is so awesome, it can have 28, 29, or
  even 30 days!

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The Second Calendar Month

• February is the second month of the year in the
  Gregorian Calendar. It is the shortest Gregorian
  month and the only month with the length of 28 or
  29 days. The month has 29 days in leap years,
  when the year number is divisible four (but not
  by 400). In other years the month has 28 days.

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The Julian Calendar

• The Julian calendar was introduced by Julius
  Caesar in 46 BC, taking force in 45 BC or 709 ab
  urbe condita. It was chosen after consultation
  with the Alexandrian astronomer Sosigenes and was
  probably designed to approximate the tropical
  year, known at least since Hipparchus. It has a
  regular year of 365 days divided into 12 months,
  and a leap day is added every 4 years, hence its
  average year is 365.25 days. The calendar
  remained in use into the 20th century in some
  countries and is still used by many national
  Orthodox churches.

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Problems with the Julian Calendar ?

• However with this scheme too many leap days are
  added with respect to the astronomical seasons,
  which on average occur earlier in the calendar by
  about 11 minutes per year. It is said that Caesar
  was aware of the discrepancy, but felt it was of
  little importance. In the 16th century the
  Gregorian calendar reform was introduced to
  improve its accuracy with respect to the time of
  the vernal equinox and the synodic month (for
  Easter). Sometimes the reference Old Style or
  O.S., as opposed to 'New Style' for the Gregorian
  Calendar, is used when there is a confusion about
  which date is found in a text

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The Gregorian Calendar

• The Gregorian calendar is the calendar currently
  used in the Western world. A modification of the
  Julian calendar, it was first proposed by the
  Neapolitan doctor Aloysius Lilius, and was
  decreed by Pope Gregory XIII, for whom it was
  named, on February 24, 1582 (Note The papal bull
  Inter gravissimas was signed in the year 1581 for
  unknown reasons, but printed on 1 March in 1582.
  But other contemporaneous papal bulls have years
  that do not agree with March years, let alone
  papal years or other types of years.)

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Why is February called that?

• February was named for the Roman god Februus, the
  god of purification. January and February were
  the last two months to be added to the Roman
  calendar, since the Romans originally considered
  winter a monthless period. This change was made
  by Numa Pompilius about 700 BCE in order to bring
  the calendar in line with a standard lunar year.

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Numa Pompilius- Great Man!

• According to legend, Numa Pompilius was the
  second of the Kings of Rome, succeeding Romulus.
  His wife, the goddess Egeria, met him by a spring
  in a sacred grove and taught him how to be a wise
  legislator. He was later celebrated for his
  piety. Wishing to show his favour, the god Mars
  caused a shield to fall from the sky on the
  Palatine Hill, which had letters of prophecy
  written on it, and in which the fate of Rome as a
  city was tied up

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Intercalary month? Whats that?

• February was nominally the last month of the
  Roman calendar, as the year originally began in
  March. At certain intervals Roman priests
  inserted an intercalary month, Mercedonius, after
  February to realign the year with the seasons.

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Mercedonius Explained

• Mercedonius was a month in the ancient Roman
  calendar. Also known as Intercalaris it was a
  intercalary month of 22 days, being inserted into
  the month of Februarius only in leap years.
• Originally this month was inserted every two
  years to realign the Numa's 355 day calendar with
  the seasons. Later a system inserting several
  months every eight years was adopted from the
  Greek calendar. Neither system reflected the true
  length of the year very well and priests often
  forgot to insert the months at the proper times.

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February and 30 days? Say What?

• In 1929 the Soviet Union introduced a
  revolutionary calendar in which every month had
  30 days and the remaining 5 or 6 days were
  monthless holidays. In 1930 and 1931, it thus had
  a February 30, but in 1932 the months regained
  their old lengths.
• Thus 1700 was not a leap year in Sweden, but both
  1704 and 1708 were leap years contrary to the
  plan. This brought the Swedish calendar one day
  ahead of the Julian calendar but still ten days
  behind the Gregorian calendar. This confusion was
  reduced when, in 1712, two leap days were added,
  thus giving that year a February 30.

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Events in February

• February 12 is Lord Faust Birthday
• February 14 is St. Valentine's Day
• February 21 is Language Martyrs' Day celebrated
  by Bengali-speaking people
• February 21 is International Mother Language Day
• In the United States, February is Black History
  Month.
• February's flower is the primrose.
• February's birthstone is the amethyst.