Re: just wait for the 9th planet
@imanidiot, the IAU seems to disagree with you:
"So the IAU does recognize official names for the major planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune) and Earth's satellite (Moon)."
Note that it is called "Moon", not "the Moon".
Calling it Luna makes you sound like somebody who read too much Heinlein.
And no, "Tellus" is not the official name of Earth.