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At 20:31 10/18/97 -0700, David Abineri wrote:
When was precession of the equinoxes first observed and how was the
observation made? When was it verified?
The discovery is attributed by Ptolemy to Hipparchus, ca. 135 BC.
Hipparchus must have had access to the measurements of an earlier
observer.
I have no copy of Hipparchus, but can finally provide this direct
quotation from "On The Precession Of The Tropic And Equinoctal Points"
by that author:
"If then, for example, Spica was formerly 8 degrees in longitude
west of the autumnal equinox and is now 6 degrees west..."