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Did you ever wonder why December has 31 days? (1997)

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Re: Did you ever wonder why December has 31 days? (1997)

#41

Post by Anon84 »

jader201 wrote: post #29

To me, the most mathematically logical way to split up the calendar would have just been something like: 01 02 03 04 05 06 07 08 09 10 11 12 31 30 31 30 31 30 30 31 30 31 30 30 -- common year 31 30 31 30 31 30 30 31 30 31 30 31 -- leap year - All months 30 or 31. - Leap month alternates between 30 and 31. - Never have more than two consecutive months with the same day. - Only time two consecutive months have the same…

Even easier. 13 months of 28 days with one or two "leap day" per year make up 365-366.

Re: Did you ever wonder why December has 31 days? (1997)

#42

Post by sltkr »

hobbes300 wrote: post #38
sltkr wrote: post #5

This is a cute story, but it lacks all sources, and it contradicts Wikipedia [1] [2]: > Commonly repeated lore has it that August has 31 days because Augustus wanted his month to match the length of Julius Caesar's July, but this is an invention of the 13th century scholar Johannes de Sacrobosco. Sextilis in fact had 31 days before it was renamed, and it was not chosen for its length (see Julian calendar). According…

Contradicting Wikipedia does not equal a lack of truth.

No, but information on Wikipedia tends to be accurate and based on reliable sources -- when a person contradicts Wikipedia and fails to provide any sources of their own, they are usually wrong. Not necessarily, of course, but often enough to say the burden of proof lies with the person making the unsubstantiated claim.

Re: Did you ever wonder why December has 31 days? (1997)

#43

Post by gabriel34 »

peapicker wrote: post #34

I vote for 30 days for all months, followed by a 5 or 6 day festival (depending) at the end of the year. ;)

I approve of this with one change: the festival would last to the second exactly as long as it would take to synchronize the calendar to our orbit around the sun (no leap years or anything).

Could you imagine a little more than five days with no representation on the calendar? Truly a "let everything go" period of time. Society would fall into chaos, no appointments could be made for those days because there is no way to address an exact point in time before the calendar reestablishment; truly an environment for a giant worldwide party.

In reality tough we would just call it the 13th month, or the minimonth and everything would go business as usual :/

Re: Did you ever wonder why December has 31 days? (1997)

#45

Post by saraid216 »

sltkr wrote: post #42
hobbes300 wrote: post #38

Earlier quoted context omitted.

Contradicting Wikipedia does not equal a lack of truth.

No, but information on Wikipedia tends to be accurate and based on reliable sources -- when a person contradicts Wikipedia and fails to provide any sources of their own, they are usually wrong. Not necessarily, of course, but often enough to say the burden of proof lies with the person making the unsubstantiated claim.

Uh. There was a source provided: 1911 Encyclopedia Britannica.

I wouldn't call that more reliable, but it's still as valid a source as Wikipedia.

Re: Did you ever wonder why December has 31 days? (1997)

#46

Post by gabriel34 »

Thiz wrote: post #39

I like the universal calendar with 13 months, all with 28 days in four weeks. One extra day at the end of the year. Another extra day for leap year.

How about no months, 52 weeks per year with a 53rd 5-day week on leap years which would also correct leap seconds and such.

I have always organized myself weekly, so does everyone around me. I think it's much more natural than months, specially because you have week-ends which mark the end of each week, but not a month-end, you just drift from one month to the other, nothing happened (except bills and paychecks and whatnot, which can also be made weekly)

Re: Did you ever wonder why December has 31 days? (1997)

#47

Post by gabriel34 »

sirn wrote: post #26
iMark wrote: post #9

True or not, it's finally given me the means to remember which months have how many days.

Interesting, I never thought of this problem before. In Thai, all month names are suffix with a word indicating number of days in a month. For example, "-khom" in "Mokkarakhom" (January) indicates 31 days, where "-yon" (e.g. Mesayon, "April") indicates 30 days. Benefit of being late-adopter allow us to name a month in a convenient way, I guess.

Interesting. What about February and leap years?

Does khom and yon have meanings?

The rest of the month's name is based on what?

Re: Did you ever wonder why December has 31 days? (1997)

#48

Post by vondur »

cedsav wrote: post #11

And it's wrong. The email is from 1997, but now you can look it up on wikipedia: http://en.wikipedia.org/wiki/Julian_calendar Short version - Julius didn't name the month after himself, the roman Senate did. There's good indications that July and August had 31 days before the reform, and February has less days because it was the last month of the year.

Not only that, but the Roman calendar was a mess from whole end of the Republic going on for the last ~100 years. The dates for some of the events listed in the Roman civil wars of Caesar had drifted from solar time pretty badly at the end (40'sBCE) and were off by month from the solar year. (The Romans has used a lunar calendar previously) In fact, members of the priesthood who determined the festival days that would bring the lunar calendar in sync with the actual solar time were often bribed to extend the year which would allow the consuls longer times in office. One of the first things Caesar did when he became the sole ruler of Rome was to reorganize the calendar around the solar year. He did so with the help of a Greek Astronomer from Alexandria. I believe the Greek astronomer made some faulty calculations regarding leap years, which is why the Gregorian calendar was instituted to fix the mistake in the 1500's.

Re: Did you ever wonder why December has 31 days? (1997)

#49

Post by zw123456 »

ghkbrew wrote: post #19
ds9 wrote: post #13

For centuries in the western world, the Christian church, which considered this to be in its purview, kept trying different calendar schemes to try to make a set of months, preferably equal, fit neatly into the year. There have been may solutions tried or proposed, and the history of this has a certain puzzle-like fascination, but it's not clear to me why people cared so much about this. Astronomical periods are OK,…

It's my understanding that the original basis for months was the lunar cycle, which is astronomical for common definitions of the word. Part of what makes picking a calendar difficult is that the ~29.5 day lunar month doesn't fit neatly into the ~365.25 day solar year. So we've ended up with succession of adjustments and fudge factors.

13 * 28 = 364, pretty close, you are left with 1.25 as a remainder, so every 4 years have a 5 day leap week.

Re: Did you ever wonder why December has 31 days? (1997)

#50

Post by baking »

iopq wrote: post #36
jader201 wrote: post #29

To me, the most mathematically logical way to split up the calendar would have just been something like: 01 02 03 04 05 06 07 08 09 10 11 12 31 30 31 30 31 30 30 31 30 31 30 30 -- common year 31 30 31 30 31 30 30 31 30 31 30 31 -- leap year - All months 30 or 31. - Leap month alternates between 30 and 31. - Never have more than two consecutive months with the same day. - Only time two consecutive months have the same…

This is close to what was done, February is the last month of the year in the Julian calendar. Only two consecutive months have the same amount of days (July/June) and the last month varies by leap year (adding an extra day at the end of the year) It's only weird that the last month got 28 due to doubling of the 31 day months instead of 30 day months

I have always felt that the 31-30-31-30-31 pattern from March through July, Repeating August through December, and then starting again in January was significant. I once wrote an extremely short assembly language routine (PDP-11 I think) for calculating the ordinal date from the calendar date that used simple integer arithmetic (multiply by 153 and divide by 5, I think) to calculate the days in the whole months starting in March.

30.6 rounds to 31

61.2 rounds to 61

91.8 rounds to 92

122.4 rounds to 122

153.0 rounds to 153 etc.

See http://www.cs.utsa.edu/~cs1063/projects/Spring2011/Project1/...

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