In spite of the addition of regular leap years, the calendar established by Julius Caesar overestimated the length of a year by 11 minutes and 15 seconds. The result was the addition of a full day every 128 years. By the sixteenth century it had accumulated an error of 10 full days, and a fix couldn’t be put off much longer.
By now the Roman Empire was history, so to speak, and the calendar issue was dropped in the lap of Pope Gregory XIII. In 1582 he decreed that the calendar be reformed by removing the excess minutes from the year, along with the 10 extra days that had piled up. Pope Gregory carried over the order of months and number of days per month from the Julian calendar, but a year would now be 365 days, with an extra day being added every 4 years, or leap year. The Roman Catholic nations of Europe fell in line quickly in adopting this system, called the Gregorian calendar.
Europe’s Protestant nations, along with the Eastern Orthodox Church, however, had other ideas. The Catholic pope wasn’t going to tell them what to do, and they stuck with the Julian calendar. That put London 10 days ahead of Paris. Protestant and Orthodox believers celebrated Christmas 13 days later than did Catholics, on the equivalent of the Julian calendar’s January 6. In fact, in some parts of Great Britain people still call that date Old Christmas Day. England also continued to celebrate New Year’s Day on March 25th instead of on the new date of January 1. Imagine what this did for business.
The result was that by 1751 England was eleven days ahead of the Continent. The situation had become so confusing that Parliament gave in to the inevitable and passed the Calendar Act to try to get back in step with the rest of the world. In an exquisitely simple maneuver, they decreed that in England and her colonies the day following September 2, 1752, would become September 14. Astonishingly, this was too difficult for many people to comprehend. They believed that the government had actually stolen 11 days from their lives, and riots broke out as the uninformed demanded that the government return their 11 days!
Although the original purpose of the Gregorian calendar was to regulate the ceremonial cycle of Christian churches, today it also serves as the international standard for civil affairs. Years are counted from the initial epoch defined by Dionysius Exiguus, a sixth-century scholar, beginning with the assumed birth of Christ—which today we know to be in error—and are divided into two classes: common years and leap years. Common years are 365 days in length. Leap years are 366 days, with February 29 inserted before March 1. Every year that can be divided by 4 is a leap year … xcept for years that can be exactly divided by 100, which are leap years only if they can be exactly divided by 400. For example, the year 2000 is a leap year, while 1900 and 2100 are not. Clear, isn’t it? I thought so.
Bede, an eighth-century English historian, is the one who began the practice of counting years backward from the year AD 1 to account for time before the birth of Jesus. The year AD 1 is preceded by the year 1 BC, without an intervening year 0. That caused all sorts of trouble for astronomers, but they came up with a solution that’s beyond our interest here. However, it should be noted that the Gregorian calendar accumulates an error of one day in roughly 2,500 years. That’s going to cause problems one of these days, but at this point, no one is doing anything about it.
Today there are approximately forty different calendars in use around the world, divided into three distinct types. A solar calendar, like the Gregorian calendar, is designed to synchronize with what is called the tropical year, and days are regularly added to correct accumulated errors. A lunar calendar, like the Islamic calendar, strictly follows the lunar phase cycle, with the result that its months continue to shift in relation to the Gregorian calendar. Lunisolar calendars, like the Hebrew and Chinese calendars, base months on the lunar phase cycle, but insert an entire month every few years to correct their built-in error.
As long as we’re talking about sun and moon cycles, let’s assume you have a romantic scene going, your handsome hero and beautiful heroine are in a clinch gazing longingly at each other, drenched by silvery light of a full moon, their hair blowing in the warm breezes of that white sand beach in Key West on New Year’s Day, and he bends to her and their lips draw closer and….
Hold it! Come to think of it, would there have been a full moon on New Year’s day in the year your story takes place? And if there was, would it have been high in the sky at that exact hour? ACK! Before you can complete your scene, you have to find out what phase the moon was in on the night in question as well as when it would appear to rise and set in Key West.
If you’re obsessive about making sure every detail in your story is accurate and you haven’t already discovered these sites for calculating the phases of the moon and the position of the sun on a specific date and time, here are the two best sites I’ve found for digging up historical data. For that matter, for all you sci-fi folks, it would also work for the future—but only for earth.
The US Naval Observatory offers a wealth of information about all things celestial. Click on Complete Sun and Moon to look up historical as well as contemporary and future dates.
The NASA Eclipse Home Page gives a readout of moon phases beginning in 1701.
Well, that’s all for today. Don’t forget to post your comments to be entered in this week’s drawing for a free copy of Deeanne Gist’s A Bride most Begrudging. And be sure to stop by again tomorrow for Michelle Sutton’s review of Loving Liza Jane by Sharlene Maclaren, due in bookstores in April.
By now the Roman Empire was history, so to speak, and the calendar issue was dropped in the lap of Pope Gregory XIII. In 1582 he decreed that the calendar be reformed by removing the excess minutes from the year, along with the 10 extra days that had piled up. Pope Gregory carried over the order of months and number of days per month from the Julian calendar, but a year would now be 365 days, with an extra day being added every 4 years, or leap year. The Roman Catholic nations of Europe fell in line quickly in adopting this system, called the Gregorian calendar.
Europe’s Protestant nations, along with the Eastern Orthodox Church, however, had other ideas. The Catholic pope wasn’t going to tell them what to do, and they stuck with the Julian calendar. That put London 10 days ahead of Paris. Protestant and Orthodox believers celebrated Christmas 13 days later than did Catholics, on the equivalent of the Julian calendar’s January 6. In fact, in some parts of Great Britain people still call that date Old Christmas Day. England also continued to celebrate New Year’s Day on March 25th instead of on the new date of January 1. Imagine what this did for business.
The result was that by 1751 England was eleven days ahead of the Continent. The situation had become so confusing that Parliament gave in to the inevitable and passed the Calendar Act to try to get back in step with the rest of the world. In an exquisitely simple maneuver, they decreed that in England and her colonies the day following September 2, 1752, would become September 14. Astonishingly, this was too difficult for many people to comprehend. They believed that the government had actually stolen 11 days from their lives, and riots broke out as the uninformed demanded that the government return their 11 days!
Although the original purpose of the Gregorian calendar was to regulate the ceremonial cycle of Christian churches, today it also serves as the international standard for civil affairs. Years are counted from the initial epoch defined by Dionysius Exiguus, a sixth-century scholar, beginning with the assumed birth of Christ—which today we know to be in error—and are divided into two classes: common years and leap years. Common years are 365 days in length. Leap years are 366 days, with February 29 inserted before March 1. Every year that can be divided by 4 is a leap year … xcept for years that can be exactly divided by 100, which are leap years only if they can be exactly divided by 400. For example, the year 2000 is a leap year, while 1900 and 2100 are not. Clear, isn’t it? I thought so.
Bede, an eighth-century English historian, is the one who began the practice of counting years backward from the year AD 1 to account for time before the birth of Jesus. The year AD 1 is preceded by the year 1 BC, without an intervening year 0. That caused all sorts of trouble for astronomers, but they came up with a solution that’s beyond our interest here. However, it should be noted that the Gregorian calendar accumulates an error of one day in roughly 2,500 years. That’s going to cause problems one of these days, but at this point, no one is doing anything about it.
Today there are approximately forty different calendars in use around the world, divided into three distinct types. A solar calendar, like the Gregorian calendar, is designed to synchronize with what is called the tropical year, and days are regularly added to correct accumulated errors. A lunar calendar, like the Islamic calendar, strictly follows the lunar phase cycle, with the result that its months continue to shift in relation to the Gregorian calendar. Lunisolar calendars, like the Hebrew and Chinese calendars, base months on the lunar phase cycle, but insert an entire month every few years to correct their built-in error.
As long as we’re talking about sun and moon cycles, let’s assume you have a romantic scene going, your handsome hero and beautiful heroine are in a clinch gazing longingly at each other, drenched by silvery light of a full moon, their hair blowing in the warm breezes of that white sand beach in Key West on New Year’s Day, and he bends to her and their lips draw closer and….
Hold it! Come to think of it, would there have been a full moon on New Year’s day in the year your story takes place? And if there was, would it have been high in the sky at that exact hour? ACK! Before you can complete your scene, you have to find out what phase the moon was in on the night in question as well as when it would appear to rise and set in Key West.
If you’re obsessive about making sure every detail in your story is accurate and you haven’t already discovered these sites for calculating the phases of the moon and the position of the sun on a specific date and time, here are the two best sites I’ve found for digging up historical data. For that matter, for all you sci-fi folks, it would also work for the future—but only for earth.
The US Naval Observatory offers a wealth of information about all things celestial. Click on Complete Sun and Moon to look up historical as well as contemporary and future dates.
The NASA Eclipse Home Page gives a readout of moon phases beginning in 1701.
Well, that’s all for today. Don’t forget to post your comments to be entered in this week’s drawing for a free copy of Deeanne Gist’s A Bride most Begrudging. And be sure to stop by again tomorrow for Michelle Sutton’s review of Loving Liza Jane by Sharlene Maclaren, due in bookstores in April.
2 comments:
Very interesting!
Becky,
I bet this is all you ever wanted to know about calendars and more. LOL!
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