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Re: Weeks

Jim,
The week is Babylonian, along with seconds and minutes. They used a lunar
calendar with the months starting when you could first see a fingernail
crescent moon. Each week corresponds to about one lunar phase (new, first
quarter, full, last quarter).
The challenge for calendar makers is that the rotation of the earth,
revolution of the moon about the earth, and the revolution of the
sun-earth system do not have any common divisors, so close approximate
relationships were used.
I have long wondered how our demand for high numerical precision evolved.

Gary

At 12:45 PM 4/9/01 -0600, you wrote:
When was the idea of a calendar week invented?


Jim Green
mailto:JMGreen@sisna.com
http://users.sisna.com/jmgreen

Gary Karshner

St. Mary's University
San Antonio, Texas
KARSHNER@STMARYTX.EDU