Encounter with Tiber

An Apollo 11 astronaut and the Nebula Award–nominated author of Directive 51 present a novel that "conveys the wonder and promise of space" (Publishers Weekly).
Born the year of the Moon landing, Chris Terence spends his life fighting to return humanity to that pinnacle. An engineering student with dreams of spaceflight, he finds upon graduation that the United States no longer has need for astronauts. Years of bureaucratic meddling have reduced the space program to a shell of itself, and it will take the greatest scientific find in history to send humanity skyward once more.
 
After years battling budget hawks, Chris finally gets his chance to walk on the Moon. While there, he finds evidence of an ancient alien civilization, the Tiberians, who visited Earth's satellite eight thousand years before. Understanding what happened to those long-forgotten travelers will define the lives of Chris and his son, as they fight against all odds to unlock the secrets of the universe.
"The collaboration of the first man to pilot a moon lander (Aldrin) with a major voice in contemporary science fiction (Barnes) has produced a fascinating chronicle of man's first encounter with alien intelligence" (Booklist).