Spock is one of the most popular characters in the Star Trek franchise. He's well-known and revered among fans, but you may not know everything about the Galaxy's favorite Vulcan. Here are ten things you may not have known about Star Trek's most popular alien.

01 of 10 The Other Spocks Nichelle Nichols as Spock (Edited). Paramount/CBS Leonard Nimoy wasn't always the first choice to play Spock, but he was in the running. In 1964, Roddenberry first approached DeForest Kelley, but Kelley turned it down. Kelley went on to play Doctor "Bones" McCoy. Roddenberry's second choice was Adam West, but West had committed to filming Robinson Crusoe on Mars. Roddenberry even auditioned Nichelle Nichols for Spock, who went on to play Uhura on the show.

02 of 10 Nimoy's a Good Alien Leonard Nimoy in "The Lieutenant". NBC Roddenberry had met Nimoy while filming the pilot for his earlier TV series The Lieutenant. Even during filming of that show, Roddenberry thought Nimoy's thin face would make a perfect alien. When Nimoy auditioned for the role of Spock, Roddenberry was sold on him again immediately.

03 of 10 Spock Originally Had Emotions Spock laughing in "The Cage". Paramount/CBS One of Spock's defining qualities is his logical and unemotional nature. However, that wasn't always the case. In the original, rejected pilot for the series, the female second-in-command Number One (originally played by Majel Barrett) was supposed to be cold and unemotional. In scenes from the unused pilot "The Cage," Spock is shown as enthusiastic and friendly. It was only when the pilot was reshot without Barrett's Number One and with a new captain that Spock took on his emotionless qualities.

04 of 10 Spock Looked Different Concept art of Spock. Paramount/CBS Spock looks very alien, but Roddenberry's original concept for Spock looked even more alien. Originally, Spock was meant to be half-Martian with a "reddish complexion." That changed when they discovered the red makeup would look black on black-and-white TVs still in use at the time. Roddenberry also wanted Spock to not eat or drink, but absorb energy through a plate in his stomach. Thankfully, he was talked out of that idea by one of the writers.

05 of 10 Spock's Full Name Spock at his Science Station. Paramount/CBS Spock's full name has never been revealed on screen. Throughout all incarnations, Spock has simply been known as Spock. However, this does not seem to be his actual name. In the classic series episode "This Side of Paradise," when asked about his name, Spock replies only that it is unpronounceable to humans. In the novel Ishmael, Spock's full name is given as S'chn T'gai Spock. However, since it was never included in any movie or TV show, it's debatable whether this is official.

06 of 10 The Studio Hated Spock Airbrushed photo of Spock. NBC/CBS One of the most controversial aspects of Star Trek proved to be Spock. With his pointed ears and eyebrows, NBC thought Spock looked too Satanic, and would cause a backlash from religious groups. The producers even discovered that NBC had sent out a sales brochure with an airbrushed photo of Spock to take out his pointed ears and eyebrows. The studio only relented when Spock began getting floods of fan mail.

07 of 10 The Vulcan Salute is Jewish Spock (Leonard Nimoy) on "The Original Series". NBC-Viacom One of the most familiar aspects of Spock is his Vulcan salute, which has the hands held up with the middle fingers spread in a "V" shape. In his autobiography I Am Not Spock, Nimoy revealed that the so-called Vulcan salute is based on an ancient Jewish gesture. He explained that he was taken to an Orthodox synagogue as a child, where a Priestly Blessing was being performed. He wasn't supposed to look, but peeked and saw the Kohanim priests holding up their hands with the thumbs together in a "V". The gesture is meant to represent the Hebrew letter "Shin." When Nimoy took on the role of Spock, he remembered the gesture and made it part of his character.

08 of 10 The Nerve Pinch Replaced Punching Vulcan nerve pinch. Paramount/CBS Another idea that came from Nimoy is Spock's signature "Vulcan nerve pinch." The ability to knock anyone unconscious by placing fingers on his enemy's neck came from a disagreement Nimoy had with a script. In "The Enemy Within," the script called for Nimoy to knock an evil duplicate of Kirk unconscious. Nimoy felt it was undignified for Spock to do that, and came up with the idea for the nerve pinch, instead.

09 of 10 Spock Could Have Been Replaced Stonn (Lawrence Montaigne) in "Amok Time". Paramount/CBS In season two of the original series, Leonard Nimoy got into a contract dispute that threatened the show. At the time, he only earned $1,500 per episode, and Shatner earned $5,000. Nimoy demanded $3,000 per episode. The producers threatened to recast the role of Spock, and even drew up a list of replacements, until Nimoy agreed to $2,500 per episode. But unbeknownst to Nimoy, Lawrence Montaigne (who played Vulcan Stonn in "Amok Time") had an option in his contract to take over as Spock if Nimoy pulled it again.

10 of 10 Spock Could Have Been in "Generations" Spock Prime from "Into Darkness". Paramount Pictures In Star Trek: Generations, William Shatner returned to play Captain Kirk. Later, Nimoy revealed a part had been written for Spock in Generations, but he turned it down. He felt the lines for Spock in the movie could have been written for anyone, and weren't "Spock-like," so he turned it down. He agreed to play the role again in 2009's Star Trek because he felt Spock's role was more critical to the story.