how did it get the name?
The noun "moon" is derived from Old English "mōna" and the usual English adjective pertaining to the Moon is "lunar", derived from the Latin word for the Moon, "lūna".
Moon
 The noun "moon" is derived from Old English "mōna",
where is the earth's moon located in the solar system UNANSWERABLE what is moon? It  is a gravity rounded astronomical body orbiting Earth and is the planet's only natural satellite.
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Moon [SEP] Name and etymology
The usual English proper name for Earth's natural satellite is simply the Moon, with a capital M. The noun "moon" is derived from Old English "mōna", which (like all its Germanic cognates) stems from Proto-Germanic "*mēnōn", which in turn comes from Proto-Indo-European "*mēnsis" "month" (from earlier "*mēnōt", genitive "*mēneses") which may be related to the verb "measure" (of time). Occasionally, the name Luna is used in scientific writing and especially in science fiction to distinguish the Earth's moon from others, while in poetry "Luna" has been used to denote personification of Earth's moon. Cynthia is another poetic name, though rare, for the Moon personified as a goddess, while Selene (literally "Moon") is the Greek goddess of the Moon.