If Apollo 12's crew were nervous, they certainly didn't let it show. Commander Pete Conrad and Lunar Module Pilot Alan Bean spent a pretty good chunk of their seven and a half cumulative hours on the lunar surface cracking jokes and having a good time. Here's a typical excerpt from their mission transcript:

Conrad: Okay, very good. "(Photograph) contingency sample area" I got. "Deploy the color chart (on an undisturbed surface)" Ho ho. Take your time, Al. (Pause) Hey, I'm learning to do it. (Pause)

Bean: (Pete belches) Houston, how does the LM look? I'm getting ready to go out the front door.

Conrad: Dum dee dum dum. (Pause) Whoops. No way I'm gonna...I wonder if I can get in the bottom of this crater hole?

...

Conrad: Dee dum dee dum. I feel like Bugs Bunny. (Pause; Giggles) (Pause)

Perhaps this is because they knew they wouldn't sink into the moon's unknown, powdery surface like quicksand, which was a real concern raised by astrophysicist and NASA consultant Dr. Tommy Gold leading up to the Apollo 11 mission. He based this theory on radio observations of the moon and passed it along to anyone who would listen, including Neil Armstrong and Buzz Aldrin.

Gold was widely mocked, but this thought was no doubt lingering in the back of the astronauts' minds as their lunar module touched down. The craft didn't disappear into the moon's surface, of course, and Armstrong was able to take his famous first step and utter those immortal words, "That's one small step for a man, one giant leap for mankind." (Armstrong insists he included "a," although it was dropped from recordings in transmission.) This downright profound statement—which he says was not planned—put the entire enterprise into focus. It also worked as a setup for Pete Conrad's first words on the moon, which, naturally, were a joke.

Pete Conrad was a Princeton educated aeronautical engineer, Navy test pilot, and all-around character. Leading up to the mission, Oriana Fallaci, an Italian journalist, said she thought the government told the astronauts what to say while on the moon. To prove this wasn't the case, Conrad told her exactly what he was going to say—and bet her five hundred bucks to prove that he was going to say it.

So when Conrad stepped from the lunar module and onto the pad to become the third man ever to walk on the moon, he made good on his promise and said those first words: "Whoopie! Man, that may have been a small one for Neil, but that's a long one for me."

Conrad was only 5'6", so his wager-winning statement also proved to be the first bit of extraterrestrial self-deprecation in human history. (A detailed account of the bet is featured in Andrew Chaikin's A Man on the Moon.)

According to Conrad, he never got paid that $500. Something tells us the story's worth far more than that.