What is "rocheworld"

Rocheworld (first published in serial form in 1982; first book publication, under the title The Flight of the Dragonfly, 1984) is a science fiction novel by Robert Forward which depicts a realistic interstellar mission using a laser driven light sail propulsion system to send the spaceship and crew of 20 5.9 light-years (ca. 34 trillion miles; ca. 56 trillion km) to the double planet that orbits Barnard's Star, which they call Rocheworld, where they make startling discoveries stranger than anything ever encountered before.

It had four sequels, written in collaboration with Julie Forward Fuller and Margaret Dodson Forward, Return to Rocheworld, Marooned on Eden, Ocean Under the Ice, and Rescued from Paradise., which detail the exploration of the other worlds in the Barnard System.