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Click on image for Figure 1 | Click on image for Figure 2 | Click on image for Figure 3 |
This mosaic of four side-by-side microscope images (one a color composite)
was acquired by the Optical Microscope, a part of the Microscopy,
Electrochemistry, and Conductivity Analyzer (MECA) instrument suite on
NASA's Phoenix Mars Lander. Taken on the ninth Martian day of the mission,
or Sol 9 (June 3, 2008), the image shows a 3 millimeter (0.12 inch)
diameter silicone target after it has been exposed to dust kicked up by
the landing. It is the highest resolution image of dust and sand ever
acquired on Mars. The silicone substrate provides a sticky surface for
holding the particles to be examined by the microscope.
Martian Particles on Microscope's Silicone Substrate
In figure 1, the particles are on a silcone substrate target 3 millimeters
(0.12 inch) in diameter, which provides a sticky surface for holding the
particles while the microscope images them. Blow-ups of four of the larger
particles are shown in the center. These particles range in size from
about 30 microns to 150 microns (from about one one-thousandth of an inch
to six one-thousandths of an inch).
Possible Nature of Particles Viewed by Mars Lander's Optical Microscope
In figure 2, the color composite on the right was acquired to examine dust
that had fallen onto an exposed surface. The translucent particle
highlighted at bottom center is of comparable size to white particles in a
Martian soil sample (upper pictures) seen two sols earlier inside the
scoop of Phoenix's Robotic Arm as imaged by the lander's Robotic Arm
Camera. The white particles may be examples of the abundant salts that
have been found in the Martian soil by previous missions. Further
investigations will be needed to determine the white material's
composition and whether translucent particles like the one in this
microscopic image are found in Martian soil samples.
Scale of Phoenix Optical Microscope Images
This set of pictures in figure 3 gives context for the size of individual
images from the Optical Microscope on NASA's Mars Phoenix Lander.
The picture in the upper left was taken on Mars by the Surface Stereo
Imager on Phoenix. It shows a portion of the microscope's sample stage
exposed to accept a sample. In this case, the sample was of dust kicked up
by the spacecraft thrusters during landers. Later samples will include
soil delivered by the Robotic Arm.
The other pictures were taken on Earth. They show close-ups of circular
substrates on which the microscopic samples rest when the microscope
images them. Each circular substrate target is 3 millimeters (about
one-tenth of an inch) in diameter. Each image taken by the microscope
covers and area 2 millimeters by 1 millimeter (0.08 inch by 0.04 inch),
the size of a large grain of sand.
The Phoenix Mission is led by the University of Arizona, Tucson, on behalf
of NASA. Project management of the mission is by NASA's Jet Propulsion
Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin
Space Systems, Denver.