outer space vs space

outer space and space both are nouns.

Word	Noun	Adjective	Verb	Adverb
outer space	Yes	No	No	No
space	Yes	No	Yes	No

As nouns, outer space and space are synonyms defined as:

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

Other hypernyms of outer space include location, infinite.

outer space (noun)	space (noun)
any location outside the Earth's atmosphere	the unlimited expanse in which everything is located
	(printing) a block of type without a raised letter; used for spacing between words or sentences
	a blank character used to separate successive words in writing or printing
	a blank area
	one of the areas between or below or above the lines of a musical staff
	an area reserved for some particular purpose
	any location outside the Earth's atmosphere
	an empty area (usually bounded in some way between things)
	the interval between two times

outer space (verb)	space (verb)
	place at intervals