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The CBS television series M*A*S*H (1972-83) ran for 11 seasons. The longest running nonfiction television show is Meet the Press which is in its 67th year. For a fictional series, The Guiding Light was on for 57 years and The Simpsons has been on the air for 25 years.
The American Soap Opera Guiding Light debuted in 1952 and lasted 57 years until 2009. It should be noted that it began as a radio show in 1937 so while the show had a 57 year TV run it actually lasted 72 years.
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1984
before television was invented :)
1982
next year
2010
September 1972