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What is the relation of weeks/months to the Earths rotation

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Full Member level 2
Jun 3, 2005
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week - year

may be this post is funny. but i dont know the answer.

duration of a day(24 hrs) and year(365 days) are calculated on the basis of revolution and rotation of the earth. what is the basis behind weeks(7 days) and month(28, 30, 31 days). any relation with earth's period?


Re: week - year

I think that the week and month are based on human needs. Isolated cultures over the past several thousand years have made these approximate time divisions.

In the middle east a few thousand years ago they had 30 day months and then an occasional leap month to get things back in synchronism. They used the moon phases as a reference.

The western calendar has unequal months because of the egomania of different Roman leaders 2000 years ago or so. They wanted the month named after them to have more days.

week - year

thinking of if there is no weeks.... then mayb our now saturday and sunday is only on the end of months?..

there will b no more "monday blues"


Re: week - year

I once saw a joke calendar with more days in a week and a month so that more things could get done.

Re: week - year

Flatulent is right all is tied to the Moon.

You see, words "moon" and "month" are relative in English. In slovenian languages "moon" and "month" are the same word spelled like "mesiats" - (it means not full moon).

Every moon cycle has near 29 days 12 hours 44 seconds, so people can not make equal lenth in days for every months. But even if you would take 12 of such months - there will be phase shifting relativly to the 1/12 of Sun year, so you need to use more than 30 days in few months per year.

Week was setted for 7 days as it is 1/4 of moon cycle: babylonian priests have found four states of moon: full, left half (decreasing), new moon, right half (growing). There was a rule to sow the grain only in growing moon, and to cut hair in decreasing, not to lend money in decreasing moon. That superstition is living for our days too.


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