[Lunar Surveyor]

This item comes from the collection of Colonel Michael R. Yunck (1918-1984), a highly decorated naval aviator and flying ace who flew multiple combat missions in the Guadalcanal Campaign in World War II. After the second World War, Yunck served as a test pilot at Naval Air Station Patuxent River in Maryland and with Air Development Squadron 5 (VX-5) at Moffett Field in California. Yunck proceeded to serve as a logistics officer of Marine Air Group 33 during the Korean War and as an operations officer of the 1st Marine Air Wing during the Vietnam War. While flying co-pilot during a helicopter mission on December 10, 1965, Yunck was critically wounded by ground fire and lost his right leg. He retired at the rank of Colonel and over the course of his career had been awarded two Silver Stars and the Distinguished Flying Cross. After retirement, he was involved in the aerospace industry and acquired this item for his personal collection.

A vernier engine from the development of the United States' first spacecraft to land on the Moon. Despite its small size, the vernier engine was instrumental as it provided propulsion for trajectory correction maneuvers as well as attitude and velocity control both before and during landing. Each vernier engine used hypergolic (self-igniting) propellant and generated 30-104 pounds of thrust for 4.8 minutes.

Like the preceding and overlapping Ranger program, the Surveyor project was an engineering experiment. The spacecraft went through several iterations in management, systems, and instrumentation before its first successful soft landing with a remote-controlled TV camera in Oceanus Procellarum on the near side of the Moon in June 1966. The present lot, a prototype, reflects the process of finalizing the engineering needed for such a historic feat and a major step towards the goal of landing humans on the Moon.

The vernier engines were made by Reaction Motors Division (RMD) of the Thiokol Chemical Corporation and were first used on Surveyor 1. The Surveyor program lasted through 1968 over the course of seven missions.

Each of the seven Surveyor spacecraft had three throttleable vernier engines, and all three needed to fire simultaneously in order to execute a controlled landing on the lunar surface. Five of the seven Surveyors launched successfully landed on the Moon, generating images and other data that contributed to the later Apollo program.