The 1968 book "Man's Conquest of Space" was issued with one DJ and then in 1972 with the updated 2nd issue, it sported a new cover image for the DJ.
So far in all my Nat Geo Special Publications (the book series) traveling and experience, this is the only title to have a different DJ used for any re-issue or revision. To my knowledge there is no mention of this variation in any of Buxbaum's, Nathan's, or Don Smith's guides.
Does anyone know of where this was documented? Also, does anyone know of another example of a Special Publication that had 2 (or more) DJ's issued? Both pics below . . .
1st edition (1968), prior to the actual moon landing:
2nd edition, revised (1972), featuring updated moon landing content:
At one time, I had two different DJ versions for the 1971 Those Inventive Americans. Thomas Edison, which is the common one and an artist rendering of the Wright Brothers. I sold the Wright Brothers copy to another collector years ago and honestly do not know if it was a one-off DJ.
Well that's very good to know, I had never chanced upon on of the Wright Brothers DJ cover. Thanks for sharing that with me Charlie!