Reviving this topic to acknowledge that astronaut Donald Deke Slayton had an Omega Speedmaster in his collection from early 1962 onwards... just as Wally Schirra and Leroy Gordo Cooper had.
By the Mercury 8 flight of Wally Schirra (Sigma 7), Deke Slayton was grounded for medical reasons and became NASA's first chief of the Astronaut Office. Here, June 1963, Slayton is seen during jungle survival training near Albrook Air Force Base on the east-side of the Panama canal, wearing an Omega Speedmaster... without bezel.
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