3. Howard Wolowitz - The Big Bang Theory (2007-Present)
I can't imagine anyone who is unfamiliar with The Big Bang Theory, but I'm sure there are a few of you out there. The basic concept of the show involves a group of four nerds (Sheldon, Leonard, Raj, and Howard) living in California. A fifth character, Penny, is a pretty would-be actress who lives across the hall from Sheldon and Leonard. Howard Wolowitz, an aerospace engineer who often performs work for NASA's space vehicles, reached the high point of his career with a trip to the space station at the end of Season 5. Serving as a payload specialist, Howard remained at the space station for several episodes of Season 6, thereby cementing his credentials as an astronaut.