During the 1960s space race he worked at the Jet Propulsion Laboratory and NASA, creating educational programs for the public to better understand the flights.
It was Cantwell who created the dramatic space opening that followed the dawn of man and bone thrown into the air in Stanley Kubrick's 2001: A Space Odyssey.
During Walter Cronkite's historic moon landing broadcast in 1969 Cantwell was on the communications line between NASA and the astronauts getting updates that he fed to Cronkite, who in return broadcasted that information to the world on live TV.
Graduated from the University of California, Los Angeles with a degree in animation.
Wrote two science fiction novels, CoreFires 1 and CoreFires 2.