>Pete,
>
> The slow clockwise rotation of the Earth's axis describes a cone
>with a half angle of approx. 23.5 deg. that is perpendicular to the
>Ecliptic. There is a small scale change as well termed Nodding or
>Nutation that is superimposed and has a period of 18.6 years.
>
> Although we like to believe we are geared to the stars, we must
>also except that there is quite a bit of slop in the drive train! The
>effect caused by precession causes the equinox direction to shift
>westward approx. 50 arc-secs per yr. This offset is apparent in the
>position of the Zodiac signs in our current epoch and which were
>originally positioned by the Babylonians. The cardinal point of the
>Vernal Equinox in Aries isn't in Aries at all. An interesting aside is
>the popular term Age of Aquarius, which is defined as when the vernal
>Equinox is in Aquarius. The same offset is true for all Zodiac signs
>relative to their original epoch. The Seasons as you mentioned would of
>course experience the same offset to the original epoch in which they
>were described.
>.....
I am not sure, if I have understood that correctly. Does that mean, that
summer also after half way of precession (in 13000 years) will be in July in
the northern hemisphere?
I think in the northern hemisphere summer is always in July, because the
beginning of spring is here always when then sun crosses declination of 0
degree from south to north (= crossing the ecliptic). The places of the
stars on then sky will change in this 13000 years.
Helmut Sonderegger
