Saturn Rukh
Saturn Rukh is a hard science fiction novel written by the United States physicist Robert L. Forward. It was first published in hardcover in March 1997 (and later in paperback in 1998) by Tor Books. Saturn Rukh is themed around human contact with alien organisms on the gaseous planet Saturn. Like many of Forward's books, the novel is a speculation of the nature of intelligent life in a non-Terran ecosystem, in this case the atmosphere of a gas giant planet.
Plot summary
In an unspecified time in the future, a multi-national consortium sends a team of six astronauts (each with the chance of earning a billion dollars if they complete their mission properly) to Saturn to establish a factory that mines helium for the production of precious "meta" (stabilized metastable helium), a powerful rocket fuel, in the planet's upper atmosphere. With only enough "meta" fuel to get them to Saturn, failure will cost them their lives. And all too soon the crew of astronauts crash-lands on a surface, which is actually the back of an enormous alien life-form they dub the Rukh, a 4-kilometer-long, bizarre sting-ray-shaped creature that "swims" through Saturn's gaseous upper atmosphere and has two brains, both male and female. When part of their apparatus is swallowed by one of these giant birdlike beings, the crew needs to find a way to communicate and to be able to cooperate with the Rukhs so that they may survive.