Pair of items signed, collectively, by four of the seven "Mercury Seven" astronauts, who were the first astronauts in United States history. Each item has been encapsulated by PSA, with the signature(s) certified as "Authentic." 1) Color photo (modern print) of the Mercury Seven astronauts posing together in their space suits. Signed in black marker along the bottom white border by Wally Schirra (grading 10/10), Gordon Cooper (8/10), and Scott Carpenter (10/10). The photo measures 8x10" and is in apparent Near Mint condition. 2) 1962 first-day cover signed on the front in black ink (9/10) by Deke Slayton. The envelope bears a February 20, 1962, Cape Canaveral postmark and bears a Project Mercury four-cent stamp. 6.5x3.5". EX-MT.