Donald Earl "Don" Messick (September 7, 1926 – October 24, 1997) was an American voice, radio, movie, and television actor. He was the voice of Scooby-Doo in "Scooby-Doo", Bam Bam Rubble in "The Flintstones", Astro the Dog in "The Jetsons", Muttley the Dog in "Wacky Races", Papa Smurf in "The Smurfs", and as Dr. Quest in "Johnny Quest".