Io. Titania. Calypso. Rhea. What do these names have in common? They're all the names of moons.
Throughout history, people have had a habit of naming moons after important or awe-inspiring figures, such as characters from Greek mythology or Shakespeare's plays. However, seeing as moon, though the word has a rich history, is used in a general sense for all moons, we have failed to do so for the moon we see indubitably the most. The moon seems rather a boring name for such a magnificent feature in our night sky.
Therefore the US should make a bid to the International Astronomical Union to change the name of the moon to Luna.