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I think John and I are visualizing the same physics, but we disagree
on word definitions.
John says the celestial sphere is not polar aligned, and I say it
is. John says the stars do not change their positions on the
celestial sphere. I say they do. This boils down to the definition
of celestial sphere. I teach astronomy even though I am only
an amateur astronomer.
"Just as we use the earth's poles and equator as reference marks on
the earth, we can use corresponding reference marks on the sky.
The celestial poles and celestial equator are defined by the earth's
rotation.
<snip>
In fact, the celestial poles and equator are the basis for a system
of precise celestial coordinates much like the system of latitude
and longitude on the earth, ...."
<snip>
"Over centuries precession has dramatic effects. For example, it
makes the celestial poles move across the sky. ... The pole is
now approaching Polaris and will be closest to it about AD 2100."