launching vs first appearance

launching and first appearance both are nouns.

Word	Noun	Adjective	Verb	Adverb
launching	Yes	No	No	No
first appearance	Yes	No	No	No

As nouns, launching and first appearance are synonyms defined as:

Other synonyms of launching include debut, entry, introduction, unveiling.

launching (noun)	first appearance (noun)
the act of propelling with force	the act of beginning something new
the act of beginning something new
the act of moving a newly built vessel into the water for the first time