The excerpt is an example of a simile.
A simile is a figurative language that aims to make the writing more colorful and interesting by using comparisons to describe an event, someone, a trait, a place, etc. And we can normally identify a simile because it has the words "like", "as" and "as in" in the sentence.
In the excerpt, the narrator uses this type of figurative language as he or she is comparing him or her self as a "watcher of the sky", and we can know for sure that it is not an example of hyperbole or metaphor because the sentence has the distinctive "like" of similes.