Calendar (book) and happy solstice!
By bnitz on Dec 21, 2006
During the days nearest the winter solstice, light shines between two buildings here at eastpoint, reflects off a pond and brightens up my office for a few minutes. At the same time, a few dozen miles north of here, the winter sunlight threads its way into the 5000 year old passage grave at Newgrange. The Newgrange alignment is almost certainly intentional, the eastpoint one is almost certainly an accident. But one thing we do share with our neolithic ancestors is a hope that the days don't continue to grow shorter. This year's winter solstice is shortly after midnight GMT on Friday December 22.
Did you ever wonder why Thirty days hath September, April, June...?" Why isn't September the seventh month, October the 8th month etc...?" Why are there 7 days in a week and why, in many languages their names seem to refer to planets and pagen gods? Why is the millenium always one year off? Why can't Christians agree on a day to celebrate Christmas? Why isn't the sun anywhere near your astrological "sun sign" constellation on your birthday? Was there really a year without a Christmas? Why does the unix command 'cal 9 1752' give the following output?1:
September 1752 S M Tu W Th F S 1 2 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30Many of these questions are answered in detail in David Ewing Duncan's book: "Calendar - Humanity's Epic Struggle to Determine a True and Accurate Year." 5000 years ago when Ireland's inhabitants built Newgrange, they had a fairly accurate way of measuring the winter day when the sun would stand still (solstice) and the days would stop becoming shorter. The Aztecs also had a complex calendar which attempted to compensate for the non-integer relationship between days, lunar months and years. The author goes into great detail on many aspects of the calendar. He explains how dogma, pride, war and other human failings eventually led to the kludge we accept as our calendar.
The author understandably glosses over many things. Newgrange/Knowth/Dowth (which together may form a winter solstice, summer solstice and equinox calendar) and similar neolithic astronomical devices could be the subject of another book. David gives just enough information on the astronomy behind the calendar without dwelling on it. I was almost surprised at the end of the book when he seemed unfamiliar with the workings of modern atomic clocks, but I shouldn't have been. David Ewing Duncan's area of expertise is history and specifically the history of this science. I would highly recommend this book. The book was written shortly before the embarassment2 we known as Y2k. It was also published before the U.S. delegation to the International Telecommunications Union (ITU) proposed to abolish leap seconds and once again, unhitch human time from earth time. I hope everyone on the ITU committee has read this book. Knowing how much time and effort was involved in getting our calendar (mostly) right, I really don't think fear of mini Y2k bugs is sufficient reason for unwravelling this connection with the clockwork of the universe.
1The gnome panel calendar doesn't agree with the unix cal calendar for September 1752. I don't know if that's a GNOME bug or if GNOME decided to use an earlier date for adoption of the Gregorian calendar. Gnome clock 2.16.1 on my desktop crashes if I set the date before 1902 or after 2037. Here we go again!
2 Of course Y2K bugs were real. I know of one company which lost well over $100,000 in the early months of the year 2000 because a runaway process was continually making long distance phone calls. But I'm convinced that average software and business practices are so buggy that many Y2k bugs remaining after Dec 31, 1999, were "lost in the noise."