Mainstream SETI scientists and ancient alien theorists don't agree on much, but one opinion they share is that the undisputed authority on the possibility of alien existence was the late Carl Sagan (1934-1996), whose voluminous writings on the subject have had a profound influence on ETI research.

But how many Carl Sagan fans know that while the renowned scientist was at Stanford University, he produced a controversial paper, funded by a NASA research grant, that concludes that ancient alien intervention may have sparked human civilization? Author Donald L. Zygutis lays out a compelling case that points to a cover-up by the Pentagon and NASA, who may have buried it soon after it was written. How significant is the Stanford paper? The answer may lie in another question: How would a science-backed theory and search strategy to guide the discovery of alien artifacts among our own ancient civilizations impact the worldwide institutions of government, religion, and culture?