Solaris

Solaris is a science fiction novel by the Polish writer Stanisław Lem, published in 1961. Its setting is a research station hovering above the planet Solaris, and its characters are scientists trying to make sense of an alien intelligence that appears to be a vast ocean covering the world. Among Lem's best-known books, it has been adapted repeatedly for film, radio and theatre.

Almost the whole planet is covered by a single mass of black, gelatinous material. Terran scientists conjecture that it is living and sentient, and they attempt to communicate with it. Kelvin arrives at the station to find the crew evasive and the station in disrepair, and the record of the century of research is stored in its library.

Then visitors start appearing: figures out of each researcher's past, solid enough to touch and impossible to keep out of the airlock. Kelvin's is a woman he loved and lost. The station's library holds a century of theories about the ocean, and none of them predicts the visitors, which is the position the novel leaves its characters in.

Lem wrote the book as a study of the limits of human understanding rather than as a first-contact adventure. Two of the better-known film versions are Andrei Tarkovsky's, from 1972, and Steven Soderbergh's, from 2002; Lem felt they moved away from the book's emphasis on the limits of human rationality.