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Name: Ian L. M.
Status: educator
Age: 50s
Location: N/A
Country: N/A
Date: 2001-2002

Several references have stated that the decrease in the earth's rotation has been determined from eclipse records. Can you suggest a reference that briefly describes how this is (was) done?

The cause of this small effect is primarily due to tidal friction caused by the moon-earth-sun gravitational interaction. I do not recall the exact web site but if you search terms like: "tidal forces" or "gravitational effects" or "tidal friction" I think you will find out there are a lot of small but measurable effects on the earth-moon-sun system.

Vince Calder

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