Claim: Albert Einstein once made a guest appearance on television's Gunsmoke.
Origins: Huh? Einstein on Gunsmoke? You've got to be kidding.
One "P.B." of Webster, Massachusetts, wasn't kidding, for in 1994 he wrote to TV Guide to inquire whether it was true that the famed physicist had once guest-starred on television's longest-running western.
If we were to take this seriously, we'd have to point out that it would have been impossible for Einstein to have appeared on Gunsmoke, as the world-famous scientist passed away on 18 April 1955, before the show (which premiered on 10 September 1955) went into production. He could have performed on the radio version of Gunsmoke, which aired from 1952 to 1961, but there is no evidence that he ever did. (A scientist with a German accent would have been a rather unlikely choice to voice a character in a Western radio drama.)
Most likely the TV Guide inquiry was the result of someone's taking a humorous remark a little too seriously. When renowned physicist Stephen Hawking appeared in a 1993 episode of Star Trek: The Next Generation, actor Brent Spiner, who portrayed the android Data, reportedly quipped that Hawking's cameo was "the most notable moment in television history since Albert Einstein guest-starred on Gunsmoke." Apparently at least one TV fan didn't notice how firmly Spiner's tongue was planted in his cheek.