Help me understand the rollover of the calendar
Each year I struggle to answer a few questions (I always have questions). What makes January 1 the first day of the year? Why aren't we using a clock and time system that makes more sense? Why aren't we using the Chinese or Aztec calendar?
As many of you know, this year we will have 1 entire extra second. For those who don't know...um...we get an extra second this year, so if you have a quartz watch, fix it. When you ask? Well, for you in the Central time zone (such as me), it is at 1:00PM today! Here is how it works. Today, my clock ticks:
12:59:5812:59:5912:59:601:00:00
How often does this happen you ask? About once every 18 months. Why? because when the Roman Catholic church put what we use as a calendar together, they were off. Fact is, they were off a lot! This is not the first Roman calendar either. We actually use the Gregorian calendar. Now for the quick history lesson...
The Roman Calendar
When Rome emerged as a world power, the difficulties of making a calendar were well known, but the Romans complicated their lives because of their superstition that even numbers were unlucky. Hence their months were 29 or 31 days long, with the exception of February, which had 28 days. However, four months of 31 days, seven months of 29 days, and one month of 28 days added up to only 355 days. Therefore the Romans invented an extra month called Mercedonius of 22 or 23 days. It was added every second year.
Even with Mercedonius, the Roman calendar eventually became so far off that Julius Caesar, advised by the astronomer Sosigenes, ordered a sweeping reform in 45 B.C. One year, made 445 days long by imperial decree, brought the calendar back in step with the seasons. Then the solar year (with the value of 365 days and 6 hours) was made the basis of the calendar. The months were 30 or 31 days in length, and to take care of the 6 hours, every fourth year was made a 366-day year. Moreover, Caesar decreed the year began with the first of January, not with the vernal equinox in late March.
This calendar was named the Julian calendar, after Julius Caesar, and it continues to be the calendar of the Eastern Orthodox churches to this day. However, despite the correction, the Julian calendar is still 111/2 minutes longer than the actual solar year, and after a number of centuries, even 111/2 minutes adds up.
The Gregorian Reform
By the 15th century the Julian calendar had drifted behind the solar calendar by about a week, so that the vernal equinox was falling around March 12 instead of around March 20. Pope Sixtus IV (who reigned from 1471 to 1484) decided that another reform was needed and called the German astronomer Regiomontanus to Rome to advise him. Regiomontanus arrived in 1475, but unfortunately he died shortly afterward, and the pope's plans for reform died with him.
Then in 1545, the Council of Trent authorized Pope Paul III to reform the calendar once more. Most of the mathematical and astronomical work was done by Father Christopher Clavius, S.J. The immediate correction, advised by Father Clavius and ordered by Pope Gregory XIII, was that Thursday, Oct. 4, 1582, was to be the last day of the Julian calendar. The next day would be Friday, Oct. 15. For long-range accuracy, a formula suggested by the Vatican librarian Aloysius Giglio was adopted: every fourth year is a leap year unless it is a century year like 1700 or 1800. Century years can be leap years only when they are divisible by 400 (e.g., 1600 and 2000). This rule eliminates three leap years in four centuries, making the calendar sufficiently accurate.
In spite of the revised leap year rule, an average calendar year is still about 26 seconds longer than the Earth's orbital period. But this discrepancy will need 3,323 years to build up to a single day.
"History of the Calendar." Infoplease.© 2000–2005 Pearson Education, publishing as Infoplease.31 Dec. 2005 http://www.infoplease.com/ipa/A0002061.html.
There are a couple other things that the calendar does not consider. One, the earth is slowing on it's axis. Second is time zones. Time zones is another creation of man that was originally created to help the railroads. What? That's right, the railroads created the need for time zones. Citys and towns all over the world used to have different times. Cities would measure their clock on solar time. So, Chicago, Illinois might be 6:30PM...Peoria, Illinois about 150 miles southwest would be 6:25PM. So, time zones were made. This is also not a terribly well thought out concept. First, it didn't take into account air travel nor computers (which they didn't have at the time).
Which brings me to my next point and I actually have one...Let's change it. Why can't we use ONE clock in the world? In a way we do anyway. All computers are set to GMT, now called UTC for Coordinated Universal Time (I didn't mix up the acronym, that's really right). If we did this, it would also eliminate the semi-yearly clock change MOST of us feel. I hate that and will discuss that in much more detail when the time comes. I don't have a problem going to work at 12:30PM and coming home at 8:30PM...Just because the clock has that time doesn't mean that is what the sun says...Maybe in my location the sun is up between 11:30AM and 1:00AM. I digress.
My solution: Lets get the "Numbers" TV show guy and Stephen Hawking (Astro-physicist) together and have them design a real calendar and real clock to avoid all of this confusion for eternity.
Oh, (stepping off my soapbox)...HAPPY NEW YEAR!
Edit @ 1:00PM: OK, my kids and I huddled around the computer watching the clock tick through from 12:59:59 to 1:00:00. I guess Microsoft didn't take into account the extra second. I do have to admit, it was more exciting than most New Year's countdowns.
After further investigation, the leap second is at 11:59:60PM UTC. Well, I guess I get to do this again at 5:59PM Central Time. Either way, Microsoft didn't account for it.
As many of you know, this year we will have 1 entire extra second. For those who don't know...um...we get an extra second this year, so if you have a quartz watch, fix it. When you ask? Well, for you in the Central time zone (such as me), it is at 1:00PM today! Here is how it works. Today, my clock ticks:
12:59:5812:59:5912:59:601:00:00
How often does this happen you ask? About once every 18 months. Why? because when the Roman Catholic church put what we use as a calendar together, they were off. Fact is, they were off a lot! This is not the first Roman calendar either. We actually use the Gregorian calendar. Now for the quick history lesson...
The Roman Calendar
When Rome emerged as a world power, the difficulties of making a calendar were well known, but the Romans complicated their lives because of their superstition that even numbers were unlucky. Hence their months were 29 or 31 days long, with the exception of February, which had 28 days. However, four months of 31 days, seven months of 29 days, and one month of 28 days added up to only 355 days. Therefore the Romans invented an extra month called Mercedonius of 22 or 23 days. It was added every second year.
Even with Mercedonius, the Roman calendar eventually became so far off that Julius Caesar, advised by the astronomer Sosigenes, ordered a sweeping reform in 45 B.C. One year, made 445 days long by imperial decree, brought the calendar back in step with the seasons. Then the solar year (with the value of 365 days and 6 hours) was made the basis of the calendar. The months were 30 or 31 days in length, and to take care of the 6 hours, every fourth year was made a 366-day year. Moreover, Caesar decreed the year began with the first of January, not with the vernal equinox in late March.
This calendar was named the Julian calendar, after Julius Caesar, and it continues to be the calendar of the Eastern Orthodox churches to this day. However, despite the correction, the Julian calendar is still 111/2 minutes longer than the actual solar year, and after a number of centuries, even 111/2 minutes adds up.
The Gregorian Reform
By the 15th century the Julian calendar had drifted behind the solar calendar by about a week, so that the vernal equinox was falling around March 12 instead of around March 20. Pope Sixtus IV (who reigned from 1471 to 1484) decided that another reform was needed and called the German astronomer Regiomontanus to Rome to advise him. Regiomontanus arrived in 1475, but unfortunately he died shortly afterward, and the pope's plans for reform died with him.
Then in 1545, the Council of Trent authorized Pope Paul III to reform the calendar once more. Most of the mathematical and astronomical work was done by Father Christopher Clavius, S.J. The immediate correction, advised by Father Clavius and ordered by Pope Gregory XIII, was that Thursday, Oct. 4, 1582, was to be the last day of the Julian calendar. The next day would be Friday, Oct. 15. For long-range accuracy, a formula suggested by the Vatican librarian Aloysius Giglio was adopted: every fourth year is a leap year unless it is a century year like 1700 or 1800. Century years can be leap years only when they are divisible by 400 (e.g., 1600 and 2000). This rule eliminates three leap years in four centuries, making the calendar sufficiently accurate.
In spite of the revised leap year rule, an average calendar year is still about 26 seconds longer than the Earth's orbital period. But this discrepancy will need 3,323 years to build up to a single day.
"History of the Calendar." Infoplease.© 2000–2005 Pearson Education, publishing as Infoplease.31 Dec. 2005 http://www.infoplease.com/ipa/A0002061.html.
There are a couple other things that the calendar does not consider. One, the earth is slowing on it's axis. Second is time zones. Time zones is another creation of man that was originally created to help the railroads. What? That's right, the railroads created the need for time zones. Citys and towns all over the world used to have different times. Cities would measure their clock on solar time. So, Chicago, Illinois might be 6:30PM...Peoria, Illinois about 150 miles southwest would be 6:25PM. So, time zones were made. This is also not a terribly well thought out concept. First, it didn't take into account air travel nor computers (which they didn't have at the time).
Which brings me to my next point and I actually have one...Let's change it. Why can't we use ONE clock in the world? In a way we do anyway. All computers are set to GMT, now called UTC for Coordinated Universal Time (I didn't mix up the acronym, that's really right). If we did this, it would also eliminate the semi-yearly clock change MOST of us feel. I hate that and will discuss that in much more detail when the time comes. I don't have a problem going to work at 12:30PM and coming home at 8:30PM...Just because the clock has that time doesn't mean that is what the sun says...Maybe in my location the sun is up between 11:30AM and 1:00AM. I digress.
My solution: Lets get the "Numbers" TV show guy and Stephen Hawking (Astro-physicist) together and have them design a real calendar and real clock to avoid all of this confusion for eternity.
Oh, (stepping off my soapbox)...HAPPY NEW YEAR!
Edit @ 1:00PM: OK, my kids and I huddled around the computer watching the clock tick through from 12:59:59 to 1:00:00. I guess Microsoft didn't take into account the extra second. I do have to admit, it was more exciting than most New Year's countdowns.
After further investigation, the leap second is at 11:59:60PM UTC. Well, I guess I get to do this again at 5:59PM Central Time. Either way, Microsoft didn't account for it.
Comments