Solaris is a science fiction novel written by Stanislaw Lem. It takes place on a space station orbiting the planet Solaris, which is covered by a mysterious ocean that exhibits strange and sentient behavior. The book follows psychologist Kris Kelvin as he tries to understand the nature of Solaris and its impact on the human crew. Solaris is a philosophical and introspective novel that explores the limits of human knowledge and the mysteries of alien intelligence.