Historic, one-of-a-kind flown shingle from the Mercury-Atlas 7 Aurora 7 spacecraft that carried astronaut Scott Carpenter around the Earth three times on May 24, 1962, famously painted with the mission emblem by Cece Bibby. The shingle measures 20″ x 19.5″, and features the burnt remnants of Bibby's painting of the 'Sigma 7' emblem: originally rendered in blue, white, orange, yellow, and red, only the white outlines generally remain, with the 'ghosts' of the "7," "Aurora" lettering, and three aurora rings still discernible. The correct "J37" and "J20" port markings remain at the bottom. The burn patterns affecting the painting, along with its orientation as compared to bolt holes and the shingle's ribbed exterior, clearly match the pre- and post-flight photographs of the Aurora 7 capsule: there is no doubt that this is the flown panel. The back of the panel is marked "Carpenter" at center. Also attached to the reverse is a segment of the thermocouple probe. The panel has several cuts along the edges, with a large segment excised from the upper right corner, where material was removed for analysis.
In order to understand the effects of reentry on the materials used for the shell of the Mercury capsule, NASA transferred this panel to Dr. John F. Radavich of Purdue University for destructive evaluation. Dr. Radavich's obituary makes note of his distinguished career as a researcher: 'His principal contribution to high temperature material technology had been his pioneering work in the transition of analytical procedures from optical to electron microscopy. In so doing, he developed preparation procedures that opened the doors to all future metallographic studies of superalloys. The current state-of-the-art practices for phase extraction and identification are dependent upon the fundamental knowledge that he developed.'
On October 3, 1962, the Lafayette Journal and Courier reported on Dr. Radavich's studies: 'A heat shingle from the space capsule which took astronaut Scott Carpenter on his orbital flight last May is being sent by the National Aeronautics and Space Administration to Purdue University for intensive study by Dr. John F. Radavich, associate professor of aeronautical and engineering sciences. An expert in super alloys, such as that composing the shingle, Dr. Radavich will subject the material to fragmentary dissection and testing in order to trace in detail what happened and how the capsule skin reacted to extreme pressures and temperatures, friction with the atmosphere, collisions with meteor dust, and other events that may have occurred during the flight…Findings from the study are expected to provide much-needed information about how the skin of the space capsule changes under space flight conditions.' This article furnished contemporaneous evidence that NASA did not anticipate return of the transferred shingle given that expectation the Aurora 7 shingle, and others similarly allocated to Dr. Radavich, were to be destructively evaluated—the 'fragmentary dissection' performed by Dr. Radavich is evident on this panel today.
The shingles of the Mercury capsules were composed of a nickel-based high temperature alloy called René 41, used due to its ability to retain high strength at extreme temperatures. Based on his expertise in this specific field, it is evident why Dr. Radavich would have been chosen to receive these shingles for study. In August 1962, he published a paper entitled 'Microstructural Changes Produced in Orbited Rene' 41 Heat Shingles,' in which he noted that the panel surfaces displayed no obvious meteorite impacts; that the outer oxide layer undergoes an enrichment of chromium oxide relative to preflight material; and that the amount of M6C carbide phase in flown material decreases relative to the TiC phase, among other observations.
This shingle is of particular importance, as it boasts the original hand-painted 'Aurora 7' insignia by Cece Bibby. In 1959, Bibby was hired by Chrysler Aerospace and soon began work as a contract artist for NASA, her workspace located just across the street from the astronaut office. Not a fan of the stencil designs on the Freedom 7 and Liberty Bell 7, John Glenn recruited Bibby in 1962 to design and paint by hand the emblem for his Friendship 7 spacecraft. In addition to Glenn, Bibby went on to create the designs for Scott Carpenter's Aurora 7 and Wally Schirra's Sigma 7 capsules, subsequently becoming the first and only woman to ascend the Mercury launch gantry and go inside the ‘white room’ that surrounded the vehicle.
