Marines.Together We Served

Wednesday, February 29, 2012

Leap Year

 
One of life’s many oddities is the every-four-year event we call Leap Year. I mean, what is this business of needing an additional day added to the month of February every four years? Why is this necessary? And why is February short-changed on the number of days in the first place?

The first thing to understand is the length of a solar year. A solar year is 8,766 hours in length. That equals 365 days PLUS almost 6 hours. The “almost six hours” must be accounted for. Multiply those almost six hours by four and you have an almost 24 hour time period.

Within a Leap Year you have a Leap Day which is added on the end of February. What about the person born on February 29th? Well, there are lots of smart-aleck remarks, and jokes about having a birthday every four years. But typically a person born on Leap Day will celebrate their birthday on February 28th or March 1st. Such a person is called a “leapling” or a “leaper.” And they normally celebrate their birthday in the off years on March 1st since this is the day following February 28th.

“In Gilbert and Sullivan's 1879 comic opera The Pirates of Penzance, Frederic the pirate apprentice (his birthday was February 29th) discovers that he is bound to serve the pirates until his 21st birthday rather than until his 21st year.” Ouch! Big difference!

Does the rest of the world operate on this calendar system? No. The calendar system most of the world uses is the Gregorian calendar. To work, Leap Year will be those years that are evenly divided by four. Since the time frame is almost six hours in a year, that time period must also be accounted for. So you multiply the 6 hours times 4 years and you have 24 hours – or 1 day. Stay with me here. Years that are evenly divisible by 100 are not Leap Years, unless they are also divisible by 400. Are you with me? Years in the past that are divisible by 100 and were Leap Years? 1600 and 2000. Years that were divisible by 100 but not 400 are 1700, 1800 and 1900. On the other hand, those years in the future (a matter which few of us will need to concern ourselves with) are 2100, 2200, 2300, 2500, 2600, 2700, 2900, and 3000. Hang in there – it gets better!

“The Gregorian calendar was designed to keep the vernal equinox on or close to March 21, so that the date of Easter (celebrated on the Sunday after the 14th day of the Moon—i.e. a full moon—that falls on or after March 21) remains correct with respect to the vernal equinox. The vernal equinox year is about 365.242374 days long (and increasing).” (http://en.wikipedia.org/wiki/Leap_year). Isn’t that perfectly clear now?

The Gregorian calendar is a modification from the ancient Romans known as the Julian calendar. The Julian calendar is based upon a lunisolar calendar, meaning it is coordinated through the phases of the moon. Many of the days are named after the syzygies of the moon. Did I lose you there? Syzygy comes from the Greek word which means being yoked together. Syzygy is pronounced: siz-uh-gee. For those who were fans of the TV show, The X-Files, there was an episode entitled, Syzygy. In astronomy a syzygy is the straight line of three celestial bodies, such as the sun, moon and earth. That’s when we experience lunar and solar eclipses.

“A leap year (or intercalary or bissextile year) is a year containing one additional day (or, in the case of lunarsolar calendars, a month) in order to keep the calendar year synchronized with the astronomical or seasonal year. Because seasons and astronomical events do not repeat in a whole number of days, a calendar that had the same number of days in each year would, over time, drift with respect to the event it was supposed to track. By occasionally inserting (or intercalating) an additional day or month into the year, the drift can be corrected. A year that is not a leap year is called a common year.” Now see? That’s not so hard to understand, is it?

All of this wild calculating occurs because the earth does not cooperate by orbiting the sun precisely in 24 hours.

And why is February short-changed on days? This occurred because of special holy days established by the Catholic Church. I’ve read it over a number of times and still don’t understand their calculations!

I find it interesting that in the first book of the Bible there’s a hint of what was to happen when God created everything. On the fourth day of creation God made the sun, moon and stars: “God said, ‘I command lights to appear in the sky and to separate day from night and to show the time for seasons, special days, and years. I command them to shine on the earth.’ And that's what happened. God made two powerful lights, the brighter one to rule the day and the other to rule the night. He also made the stars. Then God put these lights in the sky to shine on the earth, to rule day and night, and to separate light from darkness. God looked at what he had done, and it was good. Evening came and then morning--that was the fourth day.”

Notice in the Bible verses that it says God made the lights in the sky “to show the time for seasons, special days, and years.” And we still recognize these special days!

So enjoy this Leap Day today, February 29th. After all, it was God ordained! And Happy Birthday to all you “Leaplings” out there!

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