[Editor’s note: If you haven’t gotten a 2010 calendar yet, please try my Illustrator script for making your own. Its nifty! Many of my projects last year focused on time and less on mapping. It can be harder to count days than you might think!!!]
Sticklers for Symmetry Lament Imperfections in the 400-Year-Old Gregorian System; Earth’s Inconvenient Orbit
Friday marks the start of another new year, and for a small band of reformers, another missed opportunity.
For the 428th straight year, much of the world will again use the familiar Gregorian calendar. We will suffer the fiscal quarters of varying lengths and the 52 weeks that don’t quite fill the year. We will recite rhymes to recall how many days are in June, and shrug if we are asked whether Halloween is on a weekday.
Almost since Pope Gregory XIII promulgated the new calendar — itself a reform of Julius Caesar’s calendar — in 1582, proposals have bubbled up for something better.
Apostles of efficiency lament that each year needs a fresh wall calendar. The astronomically precise complain that Gregory’s leap-year formula (every four years, except centuries not divisible by 400) is erratic, and a hair off the real year’s length anyway. The financially fixated sigh that next year there will be more shopping days between Thanksgiving and Christmas than this year.
“We have a world-wide consensus about this second-rate calendar that the pope imposed 400 years ago,” Simon Cassidy, a California software engineer and amateur calendar scholar, says by telephone from New Zealand, where he is spending the northern-hemisphere winter.
Creating a calendar is like fitting a lot of round pegs into not quite as many square holes. Western tradition demands a seven-day week. Ancient custom, rooted in moon cycles, calls for a 12-month year. The Earth’s tilted axis produces four seasons. But the Earth, uncooperatively, takes 365 days, plus a tad more, to go once around the sun, and 365 is divisible by none of seven, 12 or four. And thanks to the extra bit of time — about one-fourth of a day — required for a complete orbit, leap years are needed to keep things on track.