VON BRAUN, WERNHER. TYPED LETTER SIGNED, TO ROGER CARAS REGARDING HIS INABILITY TO APPEAR IN 2001: A SPACE ODYSSEY, 1966

1 page, 8 by 10 inches, on National Aeronautics and Space Administration letterhead, dated "29 Mar 1966" and signed "Wernher von Braun" in black ink. 

A LETTER FROM THE ARCHITECT OF THE AMERICAN SPACE PROGRAM TO THE VICE PRESIDENT OF STANLEY KUBRICK'S PRODUCTION COMPANY, HAWK FILMS "This is a belated answer to your letter of February 1," von Braun begins.  "I have just learned from our Headquarters that the general policy in Headquarters is against participation of NASA personnel in movies to be released as entertainment features and that many opportunities of the same sort have been turned down in the past." 

2001: A Space Odyssey is regarded as one of the greatest and most influential films ever made, and deemed "culturally, historically, or aesthetically significant" by the United States Library of Congress.