Worried, I checked Wikipedia. It says the moon's name is The Moon. I can find barely any mentions of lunanauts in Google (and my spellchecker doesn't recognize it) and although I see things like "lunar surface", Wikipedia says that's just the adjective from the Latin name of the Moon.
I haven't been this disturbed since I learned that the word I learned for "fart" as a young kid - poop - didn't actually mean fart to anyone else, unless it was that day that I learned the lumpy vegetables I called turnips were actually rutabagas, and no-one else in the adult world was under the impression that they were turnips.
So what happened? Did I switch timestreams or move to an alternate world or something? Did I go back in time and step on a butterfly? What am I going to find out next?
If it's that the sun's name isn't really Sol, I give in. I know that Mars - it is still called Mars, right? - isn't called Ares, and I'm pretty sure the other famous one is called Venus and doesn't have a sekrit name only I know about.
Professor: "I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all."
Fry: "Oh. What's it called now?"