Jason Colavito has an informative post on the “big-business-factual-data-be-damned” approach of Ancient Aliens. The early section of his post notes connections between ancient astronaut theory and pop-culture, specifically with respect to Marvel comics.
The connections between ancient astronaut worldview and the sort of science fiction of comic books are deep. The comic book worlds pre-date the work of Sitchin and von Daniken. As Jason notes, there are secure roots in the writings of Lovecraft and others, but the more “vulgar” genre of the comic book also plays a significant role in where ancient astronaut theory really gets its “data”.
I recommend to readers two works in this regard. The first is a popular work of non-fiction. The second is a scholarly work (Univ of Chicago Press). Both are fascinating. The second, naturally, is dense and a harder read.
Christopher Knowles, Our Gods Wear Spandex: The Secret History of Comic Book Heroes