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------------- 1838 - Today is a Leap Day, February 29, 2016.
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- February 29 is an extra day this year because 2016 is divisible by 4. Whoever came up with that? Why do we need a Leap Year to keep our calendar in sync? In sync with what?
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- If we had a calendar with 364 days and exactly 52 weeks a year then each date would be on the same day of the week each year. Holidays would always fall on the same day of the week. How much simpler can you get?
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- The Earth’s orbit around the Sun does not quite cooperate. In order to do this system of calendar management we would have to add a whole week the end of December.
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- The Earth’s orbit ( years ) measured in the Earth’s rotation ( days ) do not ratio cleanly. A day is 23 hours and 56 minutes. A year is 365 days and 6 hours.
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- For centuries we have been trying to sync up days with years. The year is actually 365.2422 days long. There is no clean way to clean up these dangling fractions.
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- After many attempts since the Egyptians started it The Gregorian Calendar is the one we are using, sorta. Every year divisible by 4 we call a Leap Year and throw in an extra day, 365 to 366 days in 2016.
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- Even that does not work exactly. If a year can be divided by 400 evenly we also add a day. If not we don’t. Year 2000 yes, year 2100 no.
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- This string of math corrections will work for the next 3,300 years. Then we are going to be another day off. We want the calendar to match the seasons of the Year. The Easter Bunny won’t come in July and Santa Clause could not ride his sleigh in April.
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- So, to keep the seasons and the calendar we have been changing things since 1582. Pope Gregory XIII changed the calendar Julius Caesar started in 46 B.C. Caesar’s was a week off. So, Pope Gregory’s calendar is closer but we still have to keep tweaking it.
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- Actually, that does not bother me as much as day-light-savings changing our clocks back and forth. That government edict does not match my body clock. It is ironic is the most accurate thing we can measure. See the Reviews on atomic clocks.
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- In addition to the “Leap Day” we are going to get at ‘Leap Second” this year.
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- We won’t notice it , but, the National Standards Labs will click their Cesium beam atomic clocks ahead one second in order to keep “atomic time” in step with “ astronomical time”. You won’t notice it unless computers around the world take whole systems down. That won’t happen, right?
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- The leap second was first used in 1972. In fact, they jumped a whole 10 seconds in order to catch up.
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- It is challenging for the world’s computers to keep up with this stuff correctly. An International Standards Committee makes the decision. Then, the engineers need to react with new software. In 2012 the change brought down several major systems in the U.S.
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- Earth’s rotation is not consistent. Right now the Earth’s rotation is slowing down requiring more leap seconds, more often. Apple and Google made the leap second changes in their software. Windows just ignores it. Then, catches up at a later revision update.
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- The NY Stock Exchange closes for a half hour early to make certain system changes are all working ok.
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- The GPS is off by 19 seconds because recalculating would change position calculations inaccurately. Better to have the clocks different then for you to miss your turn. To go from GPS time to Universal Time just add 19 seconds.
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- Why not just forget trying to keep clocks in sync. Run two clocks like GPS does? If we let then drift apart they would only be off a few minutes in 100 years. So, you would be late to work. So, what? Is it worth the price of perfection?
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- California is even considering going off Daylight Savings Time. It is all about governments trying to keep up with science. People trying to keep up with changes.
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- An announcement will be made shortly, stay tuned.
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- Request these Reviews to learn more:
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- #1725 - We are running out of time. It is only strange if you think about it.
- This above Review lists 12 other reviews about “time”.
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----- 707-536-3272 ---------------- Monday, February 29, 2016 -----
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