Adastra is surrounded by the Centaurian fleet, and boarded. The entire crew is consumed by Centaurians except for Alstair, Jack Gary, Helen Bradley, and half a dozen officers. The Centaurian leader orders all the Adastra's records, equipment, and animals sent on board an automated ship, along with Gary and Bradley. While Alstair and the remaining officers pilot the Adastra to Proxima Centauri I, the Centaurian homeworld, the automated ship will be flown to Proxima Centauri II, an Earthlike world that has long since been stripped of its native animal life and abandoned by the Centaurians. After Gary and Bradley land on Proxima Centauri II and release the animals there, Alstair reaches the Centaurian homeworld. Alstair rigs the Adastra's engines to explode, setting off a chain reaction that will destroy the Centaurian homeworld and exterminate the Centaurians, leaving Gary and Bradley to await the arrival of the next ship from Earth. Reception L. Sprague de Camp dismissed the story as "bottom of the trunk", with no virtues beyond "fast action". Everett F. Bleiler reported that the story contains "some good material, some cliche, and some nonsense," concluding that it "seems much less successful" than when it was originally published. Story notes As Asimov notes in Before the Golden Age, earlier writers such as E. E. Smith had ignored the lightspeed barrier in writing about interstellar travel. Leinster not only worked within the constraints of the theory of relativity, he even calculated that a trip to Proxima Centauri would take seven years if the ship traveled under a constant acceleration and deceleration of one gravity. Leinster also notes that such an acceleration would bring the ship to a significant fraction of the speed of light, though he fails to take account of the resulting time dilation, which would reduce the subjective length of the trip by at least two years. Asimov also writes, "The thing I remember most clearly over the years about 'Proxima Centauri' is the peculiar horror I felt at the thought of a race of intelligent plants that lusted after animal food. It is almost an unfailing recipe for a startling science fiction story to begin by inverting some thoroughly accepted situation, something so ordinary as to be almost disregarded. Of course, animals eat plants, and of course, animals are quick and more or less intelligent, while plants are motionless and utterly passive (except for a few insect-eating plants,