For what it is worth, a few definitions from the American Heritage
dictionary:
celestial sphere: An imaginary sphere of infinite extent with the earth at
its center on which the stars, planets, and other heavenly bodies appear to
be located.
celestial pole: either of two diametrically opposite points at which the
extensions of the earth's axis intersect the celestial sphere.
ecliptic: 1. The apparent path of the sun among the stars; The
intersection plane of the earth's solar orbit with the celestial sphere. 2.
A great circle on a terrestrial globe inclined at an approximate angle of 23
degrees 27 minutes to the equator.
I suspect that the discussion is more over implication than explicit
definition. It looks to me as if there may be 2 variations on the
definition of celestial sphere. One of these meanings may be commonly used
by a particular group such as astronomers or amateur astronomers. The only
way to settle it may be by a poll at an astronomy meeting.
John M. Clement
Houston, TX
This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.