Astronomy Humor - Billions of Smiles 

Some TV shows set in space or with an astronomy, space travel and/or alien theme are meant to be funny and others are funny unintentionally.

My Favorite Martian was a TV show and later a movie.

Captain Tony Nelson is an astronaut. While on a mission, he discovered a mysterious bottle. Did you know that Jeannie's bellybutton was considered so provocative it was airbrushed out? 

This photo by Rob Jan is a tribute to the TV show (Flickr ID:  zero g)

Space opera is a sub-genre of science fiction that emphasizes romantic, often melodramatic adventure, set mainly or entirely in outer space, generally involving conflict between opponents possessing advanced technologies and abilities.

Quote from Wikipedia.com. Click here for entire article

 Examples:

• Star Trek and its numerous sequels
• Battlestar Gallactica