This is the closest view of the material underneath NASA's Phoenix Mars
Lander. This sample was taken from the top centimeter of the Martian soil,
and this image from the lander's Optical Microscope demonstrates its
overall composition.
The soil is mostly composed of fine orange particles, and also contains
larger grains, about a tenth of a millimeter in diameter, and of various
colors. The soil is sticky, keeping together as a slab of material on the
supporting substrate even though the substrate is tilted to the vertical.
The fine orange grains are at or below the resolution of the Optical
Microscope. Mixed into the soil is a small amount&mdashabout 0.5 percent&mdashof
white grains, possibly of a salt. The larger grains range from black to
almost transparent in appearance. At the bottom of the image, the shadows
of the Atomic Force Microscope (AFM) beams are visible. This image is 1
millimeter x 2 millimeters.
The Phoenix Mission is led by the University of Arizona, Tucson, on behalf
of NASA. Project management of the mission is by JPL, Pasadena, Calif.
Spacecraft development was by Lockheed Martin Space Systems, Denver.
