Counting on Calendars
By Joan Whetzel
Of all the ways to mark the passage of time, calendars are unique in that they mark short time periods (days and weeks), time periods of medium length (months), and long stretches of time (year). While clocks measure small (second), medium (minutes), and long time frames (hours), the time measurements that clocks register are still shorter than a day. Calendars begin with one 24 hour day and continue on to encompass an entire year. There is, however, more than one type of calendar being used. The three main calendar types are the Chinese calendar based on the cycles of the moon, the Islamic calendar centered on the lunar cycles and orbit, and the Gregorian calendar that was designed to measure the passage of time based around the sun.
The Chinese calendar holds the longest chronological time measurement record in history. It dates from the Emperor Huang Ti who introduced this zodiac based calendar in 2600 BC. The Chinese New Year begins on the new moon (the darkest night) midway between the winter solstice and the vernal equinox, placing it sometime between the end of January and the beginning of February. A leap month is added to the calendar every 2 to 3 years to keep the calendar aligned with the seasons.
The 12-year cycle of years are named after animals: rat, ox, tiger, rabbit, dragon, snake, horse, sheep, monkey, rooster, dog, and pig. The order of the named years is based on the order in which the animals were said to have appeared before Buddha after he called them. The Chinese calendar is further broken down into 12 months, named as follows: Zhēngyuè (first month), Xìngyuè (apricot blossoms), Táoyuè (peach blossoms), Méiyuè (plum ripens), Liúyuè (pomegranate ripens), Héyuè (lotus blossoms), Lányuè (orchid blossoms), Guìyuè (osmanthus blossums), Júyuè (chrysanthemum blossoms), Liángyuè (good month), Dōngyuè (winter month), and Làyuè (last month).
The Islamic (Hijri) calendar is based on the lunar cycle. It contains 12 lunar months and a total of 354 or 355 days. Since leap days are forbidden, the Islamic calendar doesn't keep up with the calendar used to make business and international day-to-day communications easier and more universal. The Islamic calendar was created to date events in Muslim countries and to be used by Muslims to decide the correct day for celebrating Islamic holy days and festivals. This calendar doesn't track with the seasons and has an annual drift of 11 to 12 days.
The Islamic calendar has 12 months named as follows: Muharran (forbidden), Safar (void), Rabi I(the first Spring), Rabi II (the second or last Spring), Jumada II(The first month of parched land), Jumada II (the second or last month of parched land), Rajab (respect, honor), Sha'bahn (scattered), Ramadan (scorched), Shawwal (raised), Dhu al-Qa'da (the one of truce), and Dhu al-Hiija (the one of pilgrimage).
The Gregorian calendar, now in use worldwide, is based on the 12 lunar months of the solar year, with 28 to 31 days forming 4 to 4 1/2 weeks. The Gregorian calendar was created by Pope Gregory XIII to include a 365 day year, with one leap day (February 29) added every fourth year to keep it on track with the Solar Year. The exception to the 4 year rule occurs with the centuries. Every fourth century year is a leap century, but the other three century years don't have a leap day added. So 2000 was a leap century but 2100, 2200 and 2300 will not be leap centuries.
TheGregorian calendar inherited a assortment of names for both the week days and the months.
The week names, which come from Norse, Greek and Roman Gods, are: Sunday (sun), Monday (moon), Tuesday (Tiw), Wednesday (Woden), Thursday (Thor), Friday (Frigg), and Saturday (Seater, or Saturn).
The names of the months come from the Romans and Etruscans, and include: January (Janus), February (Februus), March (Mars), April (root word meaning "other"; or the 2nd moth of a year beginning in March), May (Maia Maiestras), June (Juno), July (Julius Caesar), August (Augustus Caesar), September (7th month of Romulus), October (8th month of Romulus), November (9th month of Romulus), December (10th month of Romulus). As you might have guessed, previous calendars had ten months, but the calendar was changed to 12 months, leaving the last four month names in place.
There's a Mnemonic poem that can be recited to help remember how many days are held by each month in the Gregorian calendar.
Thirty days hath September,
April, June, and November.
All the rest have thirty-one,
Excepting February alone,
Which hath twenty-eight days clear,
And twenty-nine in each leap year.
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