astrophysicist vs uranologist

astrophysicist and uranologist both are nouns.

Word	Noun	Adjective	Verb	Adverb
astrophysicist	Yes	No	No	No
uranologist	Yes	No	No	No

As nouns, uranologist is a hypernym of astrophysicist; that is, uranologist is a word with a broader meaning than astrophysicist:

astrophysicist: an astronomer who studies the physical properties of celestial bodies
uranologist: a physicist who studies astronomy

Other hypernyms of astrophysicist include astronomer, stargazer.

astrophysicist (noun)	uranologist (noun)
an astronomer who studies the physical properties of celestial bodies	a physicist who studies astronomy