CBS announced the cancellation of “The Big Bang Theory” series after the 12th season. The show first aired in 2007 on CBS. Sources say that it was Jim Parsons, the actor who portrays Sheldon Cooper on the show, who did not want to continue with the show. The last season will premiere Sept. 24 on CBS. The series will end its run with 279 episodes next May. “The Big Bang Theory” does have a spin off called “Young Sheldon” that premiered September of last year that shows Sheldon Cooper’s childhood. It has not been announced if Parsons will continue his work with the spin off, which he narrates.