astrodynamics vs astronomy

astrodynamics and astronomy both are nouns.

Word	Noun	Adjective	Verb	Adverb
astrodynamics	Yes	No	No	No
astronomy	Yes	No	No	No

As nouns, astronomy is a hypernym of astrodynamics; that is, astronomy is a word with a broader meaning than astrodynamics:

astrodynamics: the branch of astronomy that studies the motion of natural and artificial bodies in space
astronomy: the branch of physics that studies celestial bodies and the universe as a whole

Other hypernyms of astrodynamics include uranology.

astrodynamics (noun)	astronomy (noun)
the branch of astronomy that studies the motion of natural and artificial bodies in space	the branch of physics that studies celestial bodies and the universe as a whole