extraterrestrial object vs existence

extraterrestrial object and existence both are nouns.

Word	Noun	Adjective	Verb	Adverb
extraterrestrial object	Yes	No	No	No
existence	Yes	No	No	No

extraterrestrial object (noun)	existence (noun)
a natural object existing outside the earth and outside the earth's atmosphere	everything that exists anywhere
	the state or fact of existing