Rocheworld (first published in serial form in 1982; first book publication, under the title The Flight of the Dragonfly, 1984)[1] 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 a crew of 20 on a one-way journey of 5.9 light-years (ca.

56 trillion km) to explore a double planet that orbits Barnard's Star, which they call Rocheworld, and where they make many startling discoveries.

A small group of civilian and military personnel carries out humanity's first crewed mission to another star system.

The journey lasts 40 years, but the crew uses a drug called "No-Die," which slows their aging process, whilst lowering their effective I.Q.

Unable to take off, the crew uses the plane's lift fans as propellers to make their way to the inner pole of the double planet, where the gravitation from Roche will help them to break free and return to the lander.

While making this journey, the Dragonfly attracts the attention of one of the native species of the planet: the very intelligent but non-technological Flouwen.

The Flouwen realize the humans are travelling to the pole and warn them that they are approaching a period where the configuration of the planetary system will cause the ocean on Eau to partially flow to Roche.

The humans then realize that the interplanetary waterfall poses a threat to the lander crew remaining on Roche.

This melts an underwater glacier and floods the area with warm water, upon which the ice floats off the plane.

An epilogue is set many years later, when a follow-on mission arrives from Earth and is met by the sole surviving crew member, the others having died in accidents or from old age.

The light sail system consists of three functional parts: a powerful laser, a large focusing lens, and a giant space-sail.

Flouwen are blob-like happy-go-lucky aliens that spend their days surfing waves and working on difficult mathematical problems.

A Flouwen named Clear◊White◊Whistle, described as trying to "invent" physics and astronomy, discovers a way to see outside the water by morphing its jelly body into a crude lens.

Flouwen are also capable of morphing themselves into a hard rock-like substance when they feel the need to think about a difficult problem for an extended period.

The Christmas Bush is similar to some recursive fractal structures where the large scale shape of the robot is repeated a number of times in progressively smaller size.

To fly, the smallest rods work together like the cilia of single celled organisms to provide thrust in any direction.

James will always keep some portion of the imp in contact with the crew's skin to allow it to monitor their health by recording their temperature, pulse, etc.

Rocheworld was first published in slightly shorter form as a serial in Analog Science Fiction and Fact magazine in December 1982 through February 1983.

A revised and lengthened version was released in 1990 from Baen Books under the original title Rocheworld, marked "At Last The Complete Story!".

Dave Langford reviewed The Flight of the Dragonfly for White Dwarf #68, and stated that "It's a shame that with all this seething behind his marble brow, Forward never put across the drama and visual excitement of the events he's calculated to the eleventh decimal place.