The History Of Alpha Centauri

Earthborn and Lunarians necessarily colonise different planets. Earthborn terraform Demeter. Lunarians must live in artificial environments in low gravity as they did on the Moon but they and their technologies make these environments not merely habitable but exotically beautiful. The races cooperate:

a joint expedition to the planet Phaeton to confirm that it will be impossible to destroy it before it collides with Demeter;

joint production of antimatter on the innermost planet, Hephaistos;

a Demetrian space navy helps Phyle Ithar to defend its space habitat Zamok Sabyel against attacks by Phyles Arcen and Yanir;

joint research on further interstellar travel;

round trips to oxygen-bearing planets of 82 Eridani, Beta Hydri and HD44594 by near light speed superships each containing a Guthrie download;

a Demetrian Republic space service observer on the Lunarian expedition to the planet Dis in the Proxima system.

Anderson's imagination continues unimpeded into an indefinite future.