Country of Origin: United States of America
Overall: 13 in. long x 5 1/2 in. diameter, 5.5 lb. (33.02 x 13.97cm, 2.5kg)
Combustion chamber, concentric stainless steel shell lined with Rokide-Z ceramic coating; nozzle, molybdenum coated with a high emissivity material; a silcon carbide ring placed at the top of the combustion chamber with a silicone carbide throat insert around the internal throat; exposed surfaces of the vernier plumbing, coated with gold plate 0.001 inches thick and polished to a high luster.
This is the vernier rocket motor for the Surveyor unmanned lunar landing probe, America's first spacecraft to soft-land on the Moon. It was never flown but was test fired and probably therefore served as a developmental model. The vernier was small but of critical importance in providing propulsion for mid-course correction maneuvers and attitude and velocity control before and during the landing. It had to be absolutely reliable with restart capability. The vernier produced 30-104 pounds of thrust and was only fired for short bursts as required. The engine was used successfuly on all of the Surveyor missions from 1966 to 1968. This motor was transferred to the Smithsonian in 1979 from the NASA Jet Propulsion Laboratory.
Gift of Reaction Motors Division, Thiokol Chemical Corp.