The novel follows the story of a group of scientists and engineers who are sent to the Jovian moon of Ganymede to investigate a mysterious signal that has been detected coming from the moon. The team discovers that the signal is coming from an alien artifact, and they must unravel its secrets before the alien race that created it returns to reclaim it. The novel follows the team as they explore the alien artifact, uncovering its secrets and learning more about the alien race that created it. Along the way, they must also contend with the hostile environment of Ganymede, as well as the political machinations of the various governments involved in the mission. The novel is a thrilling exploration of the unknown, as the team races against time to uncover the secrets of the alien artifact before it is too late.
By Robert Silverberg · First published 1957 · Genre: Science Fiction, Adventure, Fantasy