The soil sample came from a trench approximately 2 inches deep.
When the robotic arm first reached that depth, it hit a hard layer of frozen soil. Two attempts to deliver samples of icy soil on days when fresh material was exposed were foiled when the samples became stuck inside the scoop.
Image: This image, taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander, shows the lander's robotic arm scoop positioned over the Wet Chemistry Lab Cell on July 6, 2008, or Sol 41, the 42nd Martian day after landing.
Photograph Courtesy NASA
Also see: NASA names 'minor' planet after Indian