Nemesis

by Isaac Asimov

The novel is set in an era in which interstellar travel is in the process of being discovered and perfected. In Chapter 2, the novel states that the year 2220 was 16 years ago. Accordingly, the bulk of the novel takes place in or around the year 2236.

Before the novel's opening, "hyper-assistance", a technology allowing travel at a little slower than the speed of light, is used to move a reclusive space station colony called Rotor from the vicinity of Earth to the newly discovered red dwarf Nemesis. There, it takes up orbit around the semi-habitable moon Erythro, named for the red light that falls on it.

It is eventually discovered that the bacterial life on Erythro forms a collective organism that possesses a form of consciousness and telepathy (a concept similar to the Gaia of Asimov's Foundation series). While the colonists argue over the direction of future colonization—down to Erythro, or up to the asteroid belts of Nemesis system—events catch up with them. Back on Earth superluminal flight is perfected, ending Rotor Colony's isolation and opening the galaxy to human exploration.

The story also relates the breakup and reunion of a family. The mother, who discovered Nemesis, and her daughter were separated from the Earthbound father when the colony departed. The father then becomes part of the hyperjump research project as a result. Important in the novel is the startling discovery that the bacterial inhabitants of Erythro collectively constitute a sentient and telepathic organism and the discovery and resolution of a massive crisis: Nemesis' trajectory threatens to gravitationally destabilize the Solar System.