aeronautics vs astronautics

aeronautics and astronautics both are nouns.

Word	Noun	Adjective	Verb	Adverb
aeronautics	Yes	No	No	No
astronautics	Yes	No	No	No

As nouns, aeronautics and astronautics are synonyms defined as:

aeronautics and astronautics: the theory and practice of navigation through air or space

aeronautics (noun)	astronautics (noun)
the theory and practice of navigation through air or space	the theory and practice of navigation through air or space