This spacecraft was the second of a series designed to achieve a soft landing on the moon and to return lunar surface photography for determining characteristics of the lunar terrain for Apollo lunar landing missions. It was also equipped to return data on radar reflectivity of the lunar surface, bearing strength of the lunar surface, and spacecraft temperatures for use in the analysis of lunar surface temperatures. The target area proposed was within Sinus Medii. During the midcourse maneuver, one vernier engine failed to ignite, resulting in an unbalanced thrust that caused the spacecraft to tumble. Attempts to salvage the mission failed. The Surveyor program involved building and launching 7 Surveyor spacecraft to the Moon at a total cost of $469 million.

References
http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1966-084A