Easter

Pope Gregory XIII

It's December 31st, so naturally I'm writing a post about... Easter. Why, you ask? As we prepare to turn the page on 2009, I wondered what genius to thank for our 12 month year of 28, 29, 30 or 31 days. I haven't found all of the answers I was looking for, but I did find quite a bit.

The ancient Roman calendar consisted of 10 months, some of which carry over to today. September, October, November and December, as you can see by their prefixes, corresponded to the seventh, eighth, ninth and tenth months of the Roman calendar. The 12 month Julian calendar was introduced by Julius Caesar in 56BC, after consulting with an Egyptian astrologer. July was named for Caesar. King Augustus later changed Sextilus (the Roman sixth month) to August, and though the Julian calendar initially alternated months of 30 and 31 days, Augustus insisted August have no fewer days than July so as not to appear inferior and stole a day from February. This is why July and August are the only consecutive months of 31 days in a calendar year.

Caesar's calculations represented a year length of 365.25 days and many leap days were used to counter the inaccuracy caused by Earth's orbit. These calculations were slightly off, however, resulting in an extra day every 137 years. Over time, this caused the calendar to become out of sync with the seasons.

In 1582, the Catholic church sought calendar reform in an effort to ensure that Easter celebrations would take place close to the vernal equinox. By this time, under the Julian calendar, a drift of 10 days had already occurred. Pope Gregory XIII proposed a new calendar based on much more precise calculations that would eliminate most of the leap days and result in an extra day only once every 3,300 years. An interesting aside, here. A leap day does NOT actually occur every four years. Years evenly divisible by 100 are NOT leap years unless they are also divisible by 400. Thus, 1900 was not a leap year, 2000 was, and 2100 will not be.

The Gregorian calendar, what we use today, was adopted in October, 1582, however, in order to adjust for the Julian drift, ten days were dropped. They went to bed on October 4th and woke up the next day on the 15th. Similar occurrences took place each time a new country adopted the Gregorian calendar. Great Britain and its territories went straight from September 2, 1752 to September 14th.

So, our modern calendar was created to accommodate Easter. This is all well and good, but I still think a better system is out there waiting. Thirteen months of 28 days is only one day short. Maybe that could be New Year's Day, not belonging to a month, but just a day unto itself?

Now, why are there 7 days in a week? That's a question for another day. I'm taking the rest of the year off.