short answer to the day's burning science question

According to this article, the star-namers did have Tolkien in mind. Earendel was the name for the morning star (Venus) which Tolkien found in Old English poetry and which inspired him to create the character, originally of the same name, in The Silmarillion. In his later work he took to spelling it Eärendil, and that's how it appears in the published books. (The diaeresis over the "a" is to remind you they're two separate vowels, not a diphthong.)