Planet Earth

Calendar Redux

By Jeffrey KlugerNov 1, 1994 6:00 AM


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Of all the things Neolithic people gave us (advanced agriculture, polished stone tools, extremely silly earflap hats), few are more confusing than Stonehenge. Even thousands of years after its construction began, the mysterious ruins continue to baffle scientists.

Stonehenge--a ring of mammoth, multi-ton monoliths--is thought to have been begun in 3100 B.C. by ancient workers digging primarily with sharpened antlers taken from slaughtered animals. Excavating a plot of land this size with little more than a set of Black & Decker gardening antlers clearly wasn't a very efficient procedure: construction took 1,500 years-- far longer than the Egyptians needed to build even the largest of their pyramids, and only slightly less time than New York City needed to complete renovations on its East Fifty-first Street subway station.

While archeologists have done a pretty good job of determining when Stonehenge was built, they've been less successful at figuring out why. Originally scholars speculated that the site was a shrine or sacrificial altar. (Archeologist's rule #521: When you're unsure about the purpose of a site you've discovered, always call it a shrine of some sort. I'm just sorry I won't be around in 5,000 years to see a Burger King unearthed and described in archeological journals as the first ancient burial ground with a drive-through window and a zesty all-you-can-eat salad bar.) Ultimately some researchers rejected the Stonehenge-as-shrine theory and decided that, for all the site's enormity, it might have been nothing more dramatic than the world's first calendar. It wasn't the discovery of Garfield cartoons etched into the giant blocks that led to this conclusion, but rather the realization that if you stand inside the ring, the northeast axis of the monolith aligns with the sunrise at the summer solstice, and other stones seem to predict the location of solar and lunar eclipses.

If Stonehenge is indeed a calendar, it can't have been a very good one. Tacking a 50-ton slab of rock to the kitchen wall was difficult at best, and carrying it around in your wallet was out of the question. Not to mention that using the gigantic monoliths to make note of upcoming appointments ("Monday: Plant crops. Tuesday: Polish tools. Wednesday: Buy extremely silly earflap hat") would have been impossible without a good chisel and a lot of time.

If it's any solace to the lingering Neolithics among us, Stonehenge is by no means the world's only imperfect calendar. Ever since human beings grasped the concept of days, we've been trying to keep track of them. Over the millennia there have been Greek calendars and Latin calendars, Egyptian calendars and Roman calendars, Hebrew calendars, Byzantine calendars, Texaco calendars, and more. Timekeepers have created 10-month years, 12-month years, and 13-month years. Months have had 31 days, 28 days, and even 29.53 days. And after all that, the only thing virtually every culture in the world can agree on is that 30-days-hath- September-April-June-and-November and that you shouldn't eat oysters in months that don't contain an r.

But things may be about to get a good deal clearer, thanks to Cesare Emiliani, an emeritus marine geologist at the University of Miami. Emiliani has suggested a new, streamlined way of keeping track of the passage of years that he believes will resolve millennia of calendrical confusion. The way Emiliani sees things, the current Western calendar is off by the teensiest bit--about 10,000 years. According to his way of marking time, the present year is not 1994 but 11,994; the earliest Egyptian pyramids were built not in 2700 B.C. but in 7300; Arthur C. Clarke's eagerly awaited 2001 is not seven years in the exciting future but 9,993 years in the distant past.

"By any rational measure," Emiliani says, "human history got its start 10,000 years ago. If you want to chart time accurately and uniformly, you have to redesign the calendar around that reality."

Emiliani, more than most, has made it his business to understand the complicated history of both people and their calendars. The world's very first calendar, with the year divided into months and weeks, was drawn up some 4,000 years ago by the Babylonians; other Middle Eastern peoples duplicated the feat shortly afterward. Each month was 30 days long, corresponding roughly to a complete lunar cycle. Each week was 7 days, corresponding roughly to each waxing or waning phase in that cycle. Though every culture had its own names for the days of the week, the English forms are translations from the Latin or Norse names of the planets and the gods associated with them: Sunday, of course, was named for the sun; Monday for the moon; Tuesday for Tiw, also known as Mars (or for Tuesday Weld, I forget which); Wednesday for Woden (Mercury); Thursday for Thor (Jupiter); Friday for Frigg (Venus); Saturday for Saturn. With the advent of the telescope, many more heavenly bodies would be revealed, but once the days got their names, they generally stuck. This was probably a very good thing, since modern calendar makers would not want to have to explain to the public why they were coming up with names like Plutoday, Pulsarday, or Big Potato-Shaped Asteroid Day.

Despite the uniform numbers and similar day names, however, the ancient calendars were by no means identical. One of the biggest disagreements was over when the year should begin. Unlike our year, for example, which starts on January 1--mostly because that's when all the good New Year's parties are scheduled--the Egyptian year began at the end of July, when the Nile would routinely overflow its banks and flood the delta. This was a sensible choice since most ancient Egyptians already made a point of remembering this date, typically leaving themselves notes that read something like, "July 30: Get the hell out of delta." The nearby Babylonians and Assyrians, with no pesky Nile to worry about, began their year several months earlier, at the spring equinox.

If the Middle East was finding it difficult to choose between competing calendars, the Europeans were having trouble coming up with even one of them. It wasn't until the year we now think of as 753 B.C. that Romulus--foster son of Faustulus, nephew of Amulius, occasional business partner of the extremely gullible Credulous--founded Rome, an event used to help formulate the first European year, a truncated 10-month affair with six 30-day months and four 31-day months. The 60-day wintertime stretch that covers what we now think of as January and February went largely ignored by the Romans, mercifully leaving the calendar without two of its least pleasant months but making any planning for the holidays nearly impossible. It's thought that the second king of Rome, Numa Pompilius, named these two remaining months and established the first day of the first newly named month as the beginning of the calendar year.

But the total number of months in a year was not the only part of the calendar that underwent change in Europe. Just as malleable was the total number of days. The length of the year, of course, is based on the time it takes Earth to make one circuit around the sun. We typically think of that period as exactly 365 days. Actually, however, it takes the planet 365 days, 5 hours, 48 minutes, and 46 seconds to complete an orbit, depending on orbital perturbations, solar drag, and whether or not it had to lay over in Atlanta. For a planet that doesn't exactly have to worry about keeping a lunch date with Neptune, five or six hours doesn't mean much, but for human beings trying to keep their years straight, the extra time can add up. A quarter-day lag every 12 months throws the calendar off by a full day every four years and close to a month every century. By the time people born under one of the ancient calendars were old enough to be mentioned by Willard Scott, they wouldn't know when their birthdays were.

To correct the problem, the Alexandrine astronomer Sosigenes recommended the leap year. Adopted in 46 B.C. by then-Roman emperor Julius Caesar, the leap-year plan added a day to the calendar every four years to sop up the extra hours that had been created by Earth's unpunctual orbit. Most countries adopted the new plan enthusiastically, none more so than France, where they realized that an extra day meant three extra meals, always a welcome development in this part of Europe. (Indeed, for a time there was even talk in Paris of adding an extra leap lunch to the calendar once every week, but calorie-conscious legislators vetoed the plan.)

No matter how precise the year itself was getting, however, serious problems remained. The biggest unresolved issue was which of those tidy new years should be considered the first year ever. Cultures around the world differ passionately on the question of when the Year One occurred. The Romans considered it to be the year Romulus founded Rome, 753 B.C. For the Greeks it was 776 B.C., the date, according to tradition, of the first Olympic games. Even modern cultures have their own red-letter years that are thought of, at least informally, as the beginning of time. In Russia--nominally part of the Commonwealth of Independent States, formerly part of the Soviet Union, soon to be part of Barry Diller's QVC home-shopping empire--purists insisted that a new calendar should be issued after the communist revolution in 1918. In China, similar arguments were made after the Maoist takeover in 1948.

The biggest change of this kind, of course, took place 1,500 years ago, when newly converted Christians ran the calendrical odometer back to the birth of Jesus. In a world in which the closest thing to an information superhighway was a drifting continental plate, news of this development moved slowly. It would be another 526 years before the Christian calendar was adopted in Europe.

The problems this changeover presented went well beyond simply having to send out 526 overdue Christmas fruitcakes and backdating the petty-cash checks more than five centuries. Though nobody thought much about it at the time, the new calendar had a small but significant omission: there is no Year Zero. Ordinary mathematical ciphering would suggest that six years should elapse between, say, 3 B.C. and A.D. 3, with the B.C. calendar counting down from three to two to one to zero, and the A.D. calendar counting back up. However, since the year of Christ's birth was officially designated A.D. 1 and the year before was 1 B.C., that ostensible six-year span covers only five years. While age-sensitive Romans and Middle Easterners no doubt appreciated having a year knocked off their driver's licenses, historians of that era bristled, having to rejigger their math to make sure that an extra year was not added to the age or duration of people or events when they crossed the B.C.-A.D. boundary.

Despite this shortcoming, the Christian calendar eventually gained ascendancy throughout much of the world, and while most of us have gotten used to it, there are at least a few modern historians who still think there's room for improvement. Among them is Cesare Emiliani.

"Keeping time should be a pretty straightforward business," he says, "but the calendar we now use still has two major problems. The B.C.- A.D. boundary problem is one of them, but even if a Year Zero were added, there would still be a larger philosophical question to resolve. Is it right for nearly the entire world--much of which is Christian but most of which isn't--to mark the beginning of time from a historical moment that's significant only to Christians? The Muslims feel equally strongly about the Hegira, in A.D. 622--when Muhammad journeyed from Mecca to Medina. The Hebrews feel equally strongly about the creation. Aren't those events just as worthy of recognition?"

Emiliani proposes a two-step plan to solve both of the calendar's major shortcomings. The first step, of course, is simply to eliminate the boundary separating the pre-Christian and Christian eras. If most of the world does not acknowledge the significance of this line in the sands of time, why not just erase it? The problem, however, is that this is not as easy as it seems. If cosmologists are to be believed, the universe is approximately 15 billion years old--give or take 5 billion years. If calendrical time is pushed all the way back to the Big Bang, the date of, say, the most recent Super Bowl becomes January 30, 15,000,000,000, give or take 5 billion playoff games. Dates like this are not only awkward to say, but impossible to fit on the tiny date line of a traveler's check. The second step in rectifying the calendar once the B.C.-A.D. designation is removed thus becomes finding a uniformly acceptable date to take its place.

"There are lots of landmarks in the history of human evolution, any one of which could be used as the first year of a new calendar," says Emiliani. "The most appropriate, however, would seem to be the beginning of what geologists call the Holocene Period."

The Holocene, he explains, got under way at the end of the last ice age, about 10,000 years ago, and is generally thought of as the dawn of modern civilization. Before that, human society was an informal business, consisting mostly of loose bands of Ice Age families that hunted and gathered together and spent most of the rest of their time sitting around and waiting for somebody to invent the parka. As soon as the ice pack began to melt, however, things picked up considerably.

"It was at the beginning of the Holocene," Emiliani says, "that human beings began to master agriculture, domesticate farm animals, develop cities, and essentially do all the things that are necessary for what we think of as civilization to exist."

What Emiliani proposes, therefore, is to roll back the Year One to this momentous and secular date and let modern history flow from there. For the 1,994 years since the Christian world's Year One, calculating the date would be a simple matter of adding 10,000 to the year in question. The Dallas Cowboys thus defeated the Buffalo Bills (who, historians now believe, were already losing Super Bowls by the dawn of the Holocene) on January 30, 11,994. The Declaration of Independence was signed on July 4, 11,776. Pearl Harbor was bombed on December 7, 11,941. For events occurring before the Christian Year One, calculating the date is a simple matter of subtracting the B.C. year from 10,000 and coming up with the post-Holocene year. Thus the earliest Egyptian pyramids, which are thought to have been built in about 2700 B.C., would now have the year 7300 chiseled into their cornerstones. The city of Troy, which was founded in 1100 B.C., would have to have its municipal charter amended to read 8900.

"Such a wholesale change of historical milestones would take a little getting used to," Emiliani admits, "but it wouldn't require a lot of rote memorization. The mathematical conversion is so easy that as long as you knew the old B.C. or A.D. date, you'd be fine."

Perhaps the only drawback to Emiliani's plan concerns the difficulty inherent in pronouncing and writing all the new years. For a culture that routinely reduces "1957 Chevrolet" to "'57 Chevy," "1906" to "aught-six," and "Dwight David Eisenhower" to "Ike," making things less rather than more simplistic is not a familiar state of affairs. To reduce the public's resistance to adopting the new plan, Emiliani thus proposes delaying the calendrical changeover until the turn of the century, which will be the year 12,000 in the suggested new system. At that point, the first four digits of the year could be dropped in informal conversation and writing and replaced with an apostrophe. Thus the year 12,000 would become '0, the year 12,001 would become '1, and so on. In speech, the apostrophe would be silent.

"This process could be repeated each century," Emiliani says, "with the year 12,100 being informally referred to as '0, 12,101 as '1, and so on. The formal year, of course, would continue to be known by its full designation."

Tempting as Emiliani's plan seems for a global culture with its historical crazy quilt of calendars, even the most ardent reformer may want to think twice before adopting it. Would an 11,982 Cal Ripken Jr. rookie card have the same appeal as the original? Would John Glenn's three Earth orbits in 11,962 really seem so impressive for a society that had already reached the 120th century? Would you pay good money to see 12,001: A Space Odyssey? And as for the videotape you rented last summer and have been meaning to return to the store ever since? Don't look now, but they've got your credit card deposit, and you're about to become ten millennia overdue.

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