John Denver was a close friend of Jacques Yves Cousteau, and wrote another song about him but died shortly before the song was planned to be recorded. Calypso is the name of Jacques Cousteau's famous research boat that sailed around the world for oceanic conservation, but sunken shortly before Cousteau died.
A filk song exists in Star Trek fandom (and has been quoted in Chapter 8 of Diane Duane's Star Trek novel The Wounded Sky), based on John Denver's Calypso, but adapted to the voyages of the Enterprise: "To sail on a dream in the sun-fretted darkness, to soar through the starlight unfrightened alone. . . ."