+1 for Terry P. Really really love his stories.
Reading Buzz Aldrin's 'Encounter with Tiber' It jumps around a bit between viewpoints but the storyline to quote Amazon "oscillates between the careers of two human astronauts, Chris Terence and his son, Jason, on the moon and Mars, and the efforts of the Tiberians (from a planet of Alpha Centauri) to colonize Earth during prehistoric times. Chris meets his destiny while trying to retrieve a Tiberian relic from the moon. Meanwhile, the Tiberians' desperate efforts to colonize a habitable planet before their own is destroyed runs up against a host of well-depicted obstacles. Folly, prejudice, petty rivalries and bureaucratic befuddlement are shown to be common to both races, which are depicted with wit and empathy." Sounds like my place of work!