Alpha Centauri vs Rigil Kent

Alpha Centauri and Rigil Kent both are nouns.

Word	Noun	Adjective	Verb	Adverb
Alpha Centauri	Yes	No	No	No
Rigil Kent	Yes	No	No	No

As nouns, Alpha Centauri and Rigil Kent are synonyms defined as:

Alpha Centauri and Rigil Kent: brightest star in Centaurus; second nearest star to the sun

Other synonyms of Alpha Centauri include Rigil.

Alpha Centauri (noun)	Rigil Kent (noun)
brightest star in Centaurus; second nearest star to the sun	brightest star in Centaurus; second nearest star to the sun