Description

This spacecraft was the fourth in a series designed to achieve a soft landing on the moon and to return photography of the lunar surface for determining characteristics of the lunar terrain for Apollo lunar landing missions. Equipment on board included a television camera and auxiliary mirrors, a soil mechanics surface sampler, strain gauges on the spacecraft landing legs, and numerous engineering sensors. After a flawless flight to the moon, radio signals from the spacecraft ceased during the terminal-descent phase om 17 July 1967, approximately 2.5 min before touchdown. Contact with the spacecraft was never reestablished, and the mission was unsuccessful. The original landing target was 0.4 N, 1.33 W, the impact site is unknown, it os possible the spacecraft exploded before impact. The Surveyor program involved building and launching 7 Surveyor spacecraft to the Moon at a total cost of $469 million.

Spacecraft and Subsytems

Instruments

Topography and Texture of Lunar Surface from TV-Camera Survey

The television camera consisted of a vidicon tube, 25- and 100-mm focal length lenses, shutters, color filters, and iris mounted along an axis inclined approximately 16 deg to the central axis of the spacecraft. The camera was mounted under a mirror that could be moved in azimuth and elevation. Camera operation was totally dependent upon receipt of the proper command structure from earth. The camera was designed for frame-by-frame coverage of the lunar surface over 360 deg in azimuth and from +40 deg above the plane normal to the camera z axis to -65 deg below this plane. Both 600-line and 200-line modes of operation were available. The 200-line mode could scan one frame each 61.8 sec, 600-line pictures could be scanned each 3.6 sec. The television images were to be displayed on a slow scan monitor coated with a long persistency phosphor. The persistency was selected to optimally match the nominal maximum frame rate. One frame of TV identification was to be received for each incoming TV frame and displayed in real time at a rate compatible with that of the incoming image. These data were to be recorded on a video magnetic tape recorder and on 70-mm film. Due to the failure of the mission, no data were returned from this experiment.

Lunar Surface Sampler

The soil mechanics surface sampler was designed to dig, scrape, and trench the lunar surface and to transport lunar surface material while being photographed so that the properties of the lunar surface could be determined. The sampler was mounted below the television camera and consisted primarily of a scoop approximately 12 cm long and 5 cm wide. The scoop consisted of a container, a sharpened blade, and an electrical motor to open and close the container. A small footpad was attached to the scoop door to present a flat surface to the lunar surface. The scoop was capable of holding a maximum quantity of approximately 3.2 cm diameter of solid lunar material and a maximum of 100 cc of granular material. The scoop was mounted on a pantograph arm that could be extended about 1.5 m or retracted close to the spacecraft motor drive. The arm could also be moved from an azimuth of +40 to -72 deg or be elevated 13 cm by motor drives. It could also be dropped onto the lunar surface under force provided by gravity and a spring. The surface sampler performed seven bearing tests, four trench tests, and 13 impact tests. Due to the failure of the mission the surface sampler was never deployed.

Launch-Orbit Information

Launch Information

Launch Date: 1967-07-14 at 11:53:00 UTC
Launch Vehicle: Atlas-Centaur
Launch Site: Cape Canaveral, United States
Decay Date: 1967-07-17
Mass: 283.0 kg

Summary