The "El Capitan" region of the rock outcrop at Meridiani Planum, Mars. This image shows fine, parallel lamination in the upper area of the rock, which also contains scattered sphere-shaped objects ranging from 1 to 2 millimeters (.04 to .08 inches) in size. There are also more abundant, scattered vugs, or small cavities, that are shaped like discs. These are about 1 centimeter (0.4 inches) long. 2/20/2004 2/20/2004 The "El Capitan" region of the rock outcrop at Meridiani Planum, Mars. 2/20/2004 The "capture magnet," which attracts atmospheric dust particles from the front deck of the rover. The lighter-colored areas in the image are clean sections of the magnet virtually free of dust, and the dark areas are places where dust has collected. Dust particles in the martian atmosphere are estimated to be about 1 micrometer in size (1/1000th of a millimeter or 1/1000th of .04 inches). The material below the magnet's aluminum surface is laid out in concentric rings, giving the image a bull's-eye appearance. The magnet was designed in this configuration to collect as much atmospheric dust as possible. Spirit and Opportunity each carry seven magnets. 2/19/2004 The Mars Exploration Rover Opportunity dragged one of its wheels back and forth across the sandy soil at Meridiani Planum to create a hole (bottom left corner) approximately 50 centimeters (19.7 inches) long by 20 centimeters (7.9 inches) wide by 9 centimeters (3.5 inches) deep. The rover's instrument deployment device, or arm, will begin studying the fresh soil at the bottom of this trench later today for clues to its mineral composition and history. Scientists chose this particular site for digging because previous data taken by the rover's miniature thermal emission spectrometer indicated that it contains crystalline hematite, a mineral that sometimes forms in the presence of water. The brightness of the newly-exposed soil is thought to be either intrinsic to the soil itself, or a reflection of the Sun. 2/19/2004 The Mars Exploration Rover Opportunity dragged one of its wheels back and forth across the sandy soil at Meridiani Planum to create a hole (bottom left corner) approximately 50 centimeters (19.7 inches) long by 20 centimeters (7.9 inches) wide by 9 centimeters (3.5 inches) deep. The rover's instrument deployment device, or arm, will begin studying the fresh soil at the bottom of this trench later today for clues to its mineral composition and history. Scientists chose this particular site for digging because previous data taken by the rover's miniature thermal emission spectrometer indicated that it contains crystalline hematite, a mineral that sometimes forms in the presence of water. The brightness of the newly-exposed soil is thought to be either intrinsic to the soil itself, or a reflection of the Sun. 2/19/2004 2/17/2004 2/17/2004 2/14/2004 2/12/2004 2/9/2004 2/8/2004