Bob Keeshan
Robert James Keeshan (June 27, 1927 – January 23, 2004) was an American television producer and actor. He created and played the title role in the children's television program Captain Kangaroo, which ran from 1955 to 1984, the longest-running nationally broadcast children's television program of its day. He also played the original Clarabell the Clown on the Howdy Doody television program.
Source: Wikipedia