It seems that von Braun's desk was not always as
tidy as it is today: On my first visit (before I discovered tripods and
had to rely on my point & shoot camera's pop-up flash), his desk was a good
deal more cluttered. It seems that several of the same items were on it as are
today (e.g., it appears that the Chronology and copy of The
Mars Project, as well as the slide rule, were already on his
desk at that time), but it appears that the Mars globe has been demoted from
his desk to a bookshelf.
Perhaps newer museum staff members thought that von Braun would have approved
of the "clean desk" management fad?