space agency vs authority

space agency and authority both are nouns.

Word	Noun	Adjective	Verb	Adverb
space agency	Yes	No	No	No
authority	Yes	No	No	No

As nouns, authority is a hypernym of space agency; that is, authority is a word with a broader meaning than space agency:

Other hypernyms of space agency include agency, bureau, federal agency, government agency, office.

space agency (noun)	authority (noun)
an organization dedicated to the exploration of space.	the power or right to give orders or make decisions
	official permission or approval
	freedom from doubt; belief in yourself and your abilities
	an authoritative written work
	an administrative unit of government
	an expert whose views are taken as definitive
	(usually plural) persons who exercise (administrative) control over others