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 NASA's Deep Space Network has received a signal confirming that Mars Exploration Rover Spirit is rolling to a stop on the surface of Mars. (9:00 pm PST).
The rover is equipped with three stereoscopic cameras and expected to send back photos soon.
The Panoramic Camera will view the surface using two high-resolution color stereo cameras to complement the rover's navigation cameras. Delivering panoramas of the martian surface with unprecedented detail, the instrument's narrow-angle optics provide angular resolution more than three times higher than that of the Mars Pathfinder cameras. The camera's images will help scientists decide what rocks and soils to analyze in detail, and will provide information on surface features, the distribution and shape of nearby rocks, and the presence of features carved by ancient waterway s. The camera's two eyes sit 30 centimeters (12 inches) apart, about 1.5 meters (5 feet) above ground level on the rover's mast. The instrument carries 14 different types of filters, allowing not only full-color images but also spectral analysis of minerals and the atmosphere. Each exposure of each eye produces a digital image 1,028 pixels wide by 1,028 pixels wide. Full-circle panoramas will be mosaics about 24 frames wide and four frames high, for a combined image full of fine detail even if enlarged to the size of a giant movie screen.
Hazard-Identification Cameras ride low on the front and rear of the rover. The cameras are in stereo pairs at each location in order to produce threedimensional information about the terrain before or behind the rover. Each hazard-identification camera provides a fisheye wide-angle view about 120 degrees across. They are sensitive to visible light and yield black-and-white pictures. Onboard navigation software can analyze the images from these cameras to identify obstacles and avoid them. The front pair of hazard identification cameras provides position information to help movement of the rover's arm and placement of arm-mounted tools on target rocks.
The Navigation Camera is another stereo pair of black-and-white cameras. Like the panoramic camera, it sits on top of the mast and can rotate and tilt. Unlike the panoramic camera, it shoots wider-angle images (about 45 degrees across, compared with about 16 degrees across for the panoramic camera) and it does not have changeable filters to produce color images. Because of its wider field of view, the navigation camera's images can g! ive a quick full-circle view of the surroundings at each new location that the rover reaches, requiring less data-transmission time than would a full-circle set of panoramic camera images. Engineers and scientists will use those images in planning where to send the rover and where to use the science instruments for more detailed examinations.
3D-Pictures from the latest "Spirit" and "Opportunity" Missions, as well as from the first Mars-Mission (Pathfinder, 1997) are available at http://www.stereoscopy.com/mars
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