solar apex vs celestial point

solar apex and celestial point both are nouns.

Word	Noun	Adjective	Verb	Adverb
solar apex	Yes	No	No	No
celestial point	Yes	No	No	No

As nouns, celestial point is a hypernym of solar apex; that is, celestial point is a word with a broader meaning than solar apex:

solar apex: the point on the celestial sphere toward which the sun and solar system appear to be moving relative to the fixed stars
celestial point: a point in the heavens (on the celestial sphere)

solar apex (noun)	celestial point (noun)
the point on the celestial sphere toward which the sun and solar system appear to be moving relative to the fixed stars	a point in the heavens (on the celestial sphere)