|This mosaic of four side-by-side microscope images (one a color composite) was acquired by the Optical Microscope on the Phoenix 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. Image credit: NASA/JPL-Caltech/ University of Arizona.