The Lunar Excitation Season 3, Episode 23 -  Aired May 24, 2010

The Lunar Excitation

After Penny grows tired of her dim-witted date, she worries that dating Leonard has ruined her for dating normal guys. Meanwhile, Wolowitz and Koothrappali conspire to find Sheldon's perfect match online.

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Guest Stars: Sara Gilbert as Leslie Winkle, Mayim Bialik as Amy Farrah Fowler, Brian Thomas Smith as Zack, Lauri Johnson as Mrs. Gunderson

Writers: Chuck Lorre (Story), Bill Prady (Story), Maria Ferrari (Story), Lee Aronsohn (Teleplay), Steve Holland (Teleplay), Steven Molaro (Teleplay)

Director: Peter Chakos

Viewers: 15.02 million Households Rating: 9/14 Adults 18-49 Rating: 5.3/14

Available on iTunes

Episode Lists

  • Sheldon & Amy: Key Episodes Sheldon & Amy: Key Episodes

    The key moments in Sheldon & Amy's relationship including Howard & Raj setting them up, the signing of the relationship agreement, the first time they said "I love you", them breaking up and subsequently getting back together, the proposal, the wedding and winning the Nobel Prize together.

Episode Notes

  • The title refers to the guys' excitement at bouncing a laser off the moon.
  • This episode marks the first appearance of Mayim Bialik as Amy Farrah Fowler.
  • Mayim Bialik had been mentioned on the show before in "The Bat Jar Conjecture". Raj suggested they get TV's Blossom to join their physics bowl team.
  • Amy's character was originally going to be called Victoria, according to an article published before the episode was produced.

> Bazinga

As the guys get ready to perform a laser experiment on the roof of the apartment, Sheldon tells Howard that he regrets not bringing an umbrella as, with skin as fair as his, moon burn is a real possibility. When Howard asks him if that's "a Bazinga", Sheldon says it's "one of my best, don't you think?"

Episode Quotes

Zack: One question. How can you be sure it won't blow up?
Leonard: The laser?
Zack: The moon.

Leonard: Don't worry about the moon. We, we set our laser to stun.
Zack: Smart.
Leonard: Now, we'll be able to see the beam when it leaves, but it won't be strong enough when it comes back to be seen by the naked eye.
Zack: (chuckling) Naked.

Leonard: She didn't dump me. We were just in different places in the relationship.
Sheldon: I fail to see how a relationship can have the qualities of a geographical location.
Wolowitz: It's very simple. Leonard was living in a little town called "Please don't leave me", while Penny had just moved to the island of "Bye-bye!"

Leonard: Relax, it's just a dirty sock.
Sheldon: How on earth can you say "dirty sock" and "relax" in the same sentence?

Zack: Is that the laser? It's bitchin'.
Sheldon: Yes. In 1917, when Albert Einstein established the theoretic foundation for the laser in his paper "Zur Quantentheorie der Strahlung", his fondest hope was that the resultant device be bitchin'.
Zack: Well, mission accomplished!

News Stories

Title Date Posted
Episode 3.23 Ratings May 25, 2010

A strong finish to the third season of The Big Bang Theory as the show bows out in first place.  Full story

CBS Announces Season Finale April 20, 2010

CBS has revealed the details of the final episode of Season 3. Airs May 24th.  Full story


The guys are on the roof of the apartment building performing a lunar ranging experiment. When Leonard goes to Penny's apartment to see whether she wants to come watch, he finds her with Zack, who designs the menus for the Cheesecake Factory. When Zack sees their experiment, he is worried that the laser might blow up the moon. Sheldon remarks that Zack is "a man for Penny". When the experiment fails to excite Zack, Leonard mentions how it's demonstrable proof that a species put objects on the moon. Zack wonders which species that was, leading Sheldon to think Penny can actually do better than him. Penny and Zack leave with Penny feeling embarrassed by him.

Back in the apartment, Howard and Raj have the idea of setting up a dating profile for Sheldon. Early in the morning, Leonard wakes to Penny banging on the apartment door. She claims Leonard ruined her for regular guys and that before him she would never have known he was so stupid. Penny and Leonard go back to his room to have sex, with Penny telling Sheldon to put his noise canceling headphones on. Later, Penny tries to sneak out of the apartment, but she runs into Sheldon, who was disturbed by her use of the phrase "yee-haw" mid-coitus. When Leonard gets up, he wonders why Penny left without saying goodbye to him.

After Leonard and Penny bump into each other as she heads to work, Leonard suggests they catch a movie together. Penny tells him that last night was a mistake and that she's not looking to start a relationship. Back at the apartment, Howard and Raj are shocked when the dating site finds a match for Sheldon. Pretending to be Sheldon, who is still unaware of what they're doing, they reply to the email. Elsewhere, Leonard goes to see Leslie Winkle about having casual sex with her, but she slams the door on him.

Howard and Raj tell Sheldon about their dating site set up when the woman replies wanting to meet Sheldon. As Sheldon has no interest in meeting this woman and no faith in dating sites, he rejects their proposal. Raj, however, blackmails Sheldon with the dirty sock from the apartment roof. Sheldon reluctantly agrees to go on the date. Leonard returns to the apartment building drunk and goes over to Penny's. Leonard tries to initiate the same sort of meaningless sex they had the night before, but when Penny rejects him he thinks there's a double standard here.

Sheldon, Howard and Raj are at the coffee shop to meet his "perfect match", Amy Farrah Fowler. When Amy arrives, Sheldon tells her she has been taken in by the unsupportable mathematics of dating sites, and that he's only there because he's being blackmailed by a dirty sock. Amy reveals she's only there because of an agreement she has with her mother to date once a year. After Amy tells him that all forms of physical contact upto and including coitus are off the table, Sheldon offers to buy Amy a beverage.