Sunday, March 23, 2008

Happy Easter

It was a cold Easter morning for those who ventured out this morning for a sunrise service. The morning low dropped to 21F here at home.

Do you realize how early Easter is this year? As I recently learned, Easter is always the 1st Sunday after the 1st full moon after the Spring Equinox (which is March 20). This dating of Easter is based on the lunar calendar that Hebrew people used to identify passover, which is why it moves around on our Roman calendar. Found out a couple of things you might be interested in! Based on the above, Easter can actually be one day earlier (March 22) but that is pretty rare. Here 's the interesting info. This year is the earliest Easter any of us will ever see the rest of our lives! And only the most elderly of our population have ever seen it this early (95 years old or above!). And none of us have ever, or will ever, see it a day earlier!

Here are the facts:

1) The next time Easter will be this early (March 23) will be the year 2160 (152 years from now). The last time it was this early was 1913 (so if you're 95 or older, you are the only ones that were around for that!).

2) The next time it will be a day earlier, March 22, will be in the year 2285 (277 years from now). The last time it was on March 22 was 1818. So, no one alive today has or will ever see it any earlier than this year!

How to determine the date of Easter, the annual Christian celebration of Christ's resurrection, is something of a mystery to the average person. Unlike most other significant dates on the western calendar, which fall either on fixed dates (e.g., Halloween is always October 31st) or on easily-reckoned relative calendar days (e.g., Thanksgiving in the U.S. is the fourth Thursday in November), Easter moves around from year to year in order to preserve its relationship to the astronomical phenomena (i.e., the season of the year and the phase of the moon) that would have occurred at the time of the resurrection (traditionally reckoned as having taken place in 30 A.D.). In the modern era, Easter Sunday generally falls on the Sunday following the Paschal Full Moon (i.e., the first full moon of Spring in the northern hemisphere, or the first full moon occurring after the date of the vernal equinox). However, since astronomical observations are variable (e.g., the date of the full moon can vary depending upon the location of the observer), the date of Easter is typically calculated from tables. We'll dispense with an explanation of how to perform these calculations (for the curious, such an explanation can be found here) in favor of addressing the main points of the example quoted above. The earliest calendar date on which Easter can fall is March 22, and the latest date is April 25. Easter therefore takes place unusually early this year, as its 2008 date of occurrence is March 23. The last time Easter fell on so early a date was 1913, and the next time it will do so will be in the year 2160. Seeing Easter fall on the earliest possible date, March 22, is an experience that has not been, and (barring some remarkable breakthroughs in longevity) will not be, witnessed by anyone alive today: It last occurred in the year 1818, and it will not happen again until 2285. The odds are considerably better for witnessing a late Easter. Many people are still around from the last time Easter fell on April 25, an event which took place in 1943, and a good many people here today will likely still be around when Easter next falls on April 25, which will occur in 2038.