Big Joe (Project Mercury)

Big Joe 1
Big Joe 1 launch preparations

Big Joe was a subprogram of America's Project Mercury space program. It launched a single flight using an Atlas launch vehicle with a boilerplate Mercury capsule. The purpose of the Big Joe program was to prove the ablative heat shield which would be needed for the re-entry of orbital Mercury missions. The flight, Big Joe 1, occurred on September 9, 1959.

The Big Joe name has been attributed to Maxime Faget at NASA's Langley Research Center in Hampton, Virginia. It was a progression of the smaller test booster Little Joe. Faget also coined the Little Joe name basing it on its four large fins which reminded him a roll of four in craps.

The official Mercury mission numbering designation was a two-letter designation which corresponded to the launch vehicle type, followed by a dash then a one- or two-character designation of the flight/test number. The official designation for Big Joe 1 was BJ-1.

The launch vehicle used for BJ-1 (628/10-D) had a slightly different numbering scheme than those used for the later Mercury-Atlas flights.

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