"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.