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Old September 14th 03, 01:58 AM
Odysseus
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Scott Berg wrote:

Since the earth precesses in it's rotation, it's poles trace out a circle in
the stars about every 26,000 years. Right now, the north pole points to the
part of the circle including Polaris, more or less.

1) Does this circle have a specific technical name for each pole?

I'm not sure what you're asking here. The location of the pole at a
time other than the present is usually just identified by the epoch:
"the pole of 3000 BCE" or some such expression. The centre of the
circle is called the (north or south) "pole of the ecliptic".

2) Can anyone refer me to a source showing the actual predicted circle,
complete with dates? I want to be able to say things like "in year 13050
Vega will be the North Star" or whatever. A nice graphic program would be
helpful.

See the recent thread "Cosmological ?s", wherein I posted this link:

http://www.opencourse.info/astronomy/introduction/03.motion_earth/,

to a page that includes an animation covering about a third of the
precession cycle, and from which it isn't too hard to extrapolate. A
Google Images search for "precession" will likely turn up plenty more
such diagrams.

--
Odysseus