Historically important NASA/Project Mercury autographs. Project Mercury NASA letterhead autographed by 7 astronauts including 1.) Donald Kent "Deke" Slayton (1924-1993) American Air Force pilot, aeronautical engineer, test pilot, and one of the original NASA Mercury Seven astronauts. 2.) Virgil Ivan "Gus" Grissom (1926-1967) American engineer and pilot in the United States Air Force, one of the original NASA Mercury Seven astronauts. astronaut of Project Gemini, second American to fly in space in 1961. As commander of Apollo 1 died on January 27, 1967, during a pre-launch test for the Apollo 1 mission. 3.) John Herschel Glenn Jr. (1921-2016) American Marine Corps aviator, astronaut, businessman, and politician. He was the third American in space, first American to orbit the Earth, U.S. Senator from 1974 to 1999 and flew with the space shuttle in 1998 at the age of 77. 4.) Leroy Gordon Cooper Jr. (1927-2004) American aerospace engineer, test pilot, United States Air Force pilot, and the youngest of the seven original astronauts in Project Mercury piloting the longest and last Mercury spaceflight, He also was a member of Project Gemini, 5.) Walter Marty Schirra Jr. (1923-2007) American naval aviator, test pilot, one of the original seven astronauts chosen for Project Mercury, member of project Gemini and Apollo (Apollo 7). 6.) Alan Bartlett Shepard Jr. (1923-1998) American naval aviator, test pilot, one of the original seven astronauts chosen for Project Mercury, member of project Gemini and Apollo (Apollo 14). 7.) Malcolm Scott Carpenter (1925=2013) American naval aviator, test pilot, aeronautical engineer, astronaut, aquanaut, one of the Mercury Seven astronauts. Written in ink at top is "Best regards to Mr. Ed Hosking Jr.". Sheet measures 8" x 10" and presents typed note at lower left "February 1960" and exhibits some folds. Autographed lettersheet sold with photograph (7.25" x 10") of all 7 astronauts in Mercury program with signatures in negative. Provenance: George Robert Siddall (1868-1901)/ Edgar F. Hosking Jr. (1921-2005) autograph collection.