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Old 2019-05-14, 17:27   #12
ATH
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Ok, so you are averaging over the entire 400 year cycle.
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Old 2019-05-14, 18:00   #13
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Ok, so you are averaging over the entire 400 year cycle.
But he didn't account for an unpredictable amount of leap seconds, which throws the whole calculation off.

Also there is a longstanding proposal to make the years 4000, 8000, etc. common years instead of leap years, which would reduce the average length of a year from 365.2425 to 365.24225 days.

Clearly it's hopeless to try to figure this out and we should all just give up.
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Old 2019-05-14, 18:56   #14
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Quote:
Originally Posted by GP2 View Post
But he didn't account for an unpredictable amount of leap seconds, which throws the whole calculation off.

Also there is a longstanding proposal to make the years 4000, 8000, etc. common years instead of leap years, which would reduce the average length of a year from 365.2425 to 365.24225 days.

Clearly it's hopeless to try to figure this out and we should all just give up.
Neither did he take into account there are a number of definitions for the year.

People who actually care about these things, astronomers mostly, tend to use seconds or days (each of precisely 24x60x60 seconds) and have given up on years except where such imprecision is acceptable.

Last fiddled with by xilman on 2019-05-14 at 18:56
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Old 2019-05-14, 19:07   #15
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Quote:
Originally Posted by GP2 View Post
But he didn't account for an unpredictable amount of leap seconds, which throws the whole calculation off.

Also there is a longstanding proposal to make the years 4000, 8000, etc. common years instead of leap years, which would reduce the average length of a year from 365.2425 to 365.24225 days.

Clearly, it's hopeless to try to figure this out and we should all just give up.
It is all about making reasonable approximations. And while the Gregorian Calendar is not perfect (it gives us the 365.2425 days in a year approximation) it is quite good for civil administrative, government, agriculture, tourism affairs).

The next approximation would 365.242196 would require a modification in about 3300 years, when a day would have to be taken off. I guess it would be a random February 29.

Something like February of year 5200 won't be a leap year and end in the 28th instead of the 29th. I would venture a guess that if we have 30 or 40 "trump presidencies" in the next 3000 years we won't make it there and the point will be mute.

Interesting as it is we have drifted completely from the subject.

So perhaps I should lay another Enzocreti question.

When do you think R49081 will be proven a prime? Either by ECCP or by BLS/CHG factorization of R49080

Last fiddled with by rudy235 on 2019-05-14 at 19:10 Reason: Was thinking of capitalizing "trump" but decided against it.
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Old 2019-05-14, 22:15   #16
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(too late to edit) ...in the next 3000 years we won't make it there and the point will be mute moot.
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Old 2019-05-15, 04:27   #17
LaurV
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Something like February of year 5200 won't be a leap year and end in the 28th instead of the 29th.
I think we will never get to that, because leap seconds and "leap minutes" will continue to be added periodically, to compensate for "crazy years"...
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Old 2019-05-15, 11:18   #18
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The Earth's rotation and orbit are not constant, and are not changing is a constant way either. There is a certain amount of randomness in the variations. While it is expected that the days will gradually get longer as time passes, it is also possible in the "short" term for the days to get shorter. Basically it is all a big mess when one tries to compute some accurate values, there is always an unaccounted for factor (or three). So the only known way to "solve" it is to simply measure it with the best tools available and go from there.

TL;DR: Future predictions on leap-anythings will likely be altered to account for random variations currently that no one knows how to compute.

Still TL:DR: Ignore the predictions, just go with the flow.
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Old 2019-05-15, 12:27   #19
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Quote:
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Still TL:DR: Ignore the predictions, just go with the flow.
Yup. Just use the SI second and its multiples. That is well defined. Trust me, I'm an astronomer.
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