Here we have two official NASA letters from Eugene A. Cernan who was from the Apollo 17 & 10 Missions as well a letter from Edward G. Gibson who was selected as an astronaut by NASA in 1965 as part of Astronaut Group 4, the first group of scientist-astronauts. He served on the support crew of Apollo 12 before moving on to work on the development of the Skylab Space Station. Cernan Letter is from January 29th, 1973 while Gibson's letter is dated May 9th, 1974. Both... come with original NASA crests. Terms & Conditions Payment to be made by Paypal. Payments made by Paypal will only be shipped to a confirmed address. Positive feedback will be left upon completion of deal.