Photographic evidence of the successful series of commands to the Viking 1 lander on Mars that unlocked the surface sampler arm is seen in this picture. At lower left, to the right of a whitish area is a small oblong object -- the boom latch pin that had failed to drop out of the scoop assembly causing the mechanism to lock. With the pin free, the boom and scoop can now be used for the soil sampler experiments beginning in two days, including a search for microscopic life in the Martian soil. The boom latch pin is 0.2 inches in diameter and 3.2 inches long. The pin weights 0.44 ounces, fell from about three feet and impacted the surface at eight to nine feet per second producing a mini-crater with a dark ejecta blanket. These data will be studies to determine soil properties.