This week in 1966, technicians at NASA’s Marshall Space Flight Center captive-fired the F-1 engine on a first run for about 40 seconds. The engine, developed by Rocketdyne under the direction of Marshall, was propelled by a mixture of RP-1, a type of kerosene, and liquid oxygen. The engine was used in a cluster of five engines to propel the first, or S-IC, stage of the Saturn V rocket. Each engine produced 1.5 million pounds of thrust. Here, the engine is tested on the modified Saturn IB static test stand at Marshall. This July, in a series of special events, NASA is marking the 50th anniversary of the Apollo Program – the historic effort that sent the first U.S. astronauts into orbit around the Moon in 1968, and landed a dozen astronauts on the lunar surface between 1969 and 1972. For more pictures, and to connect to NASA’s remarkable history, visit the Marshall History Program’s webpage. (NASA)