Data

The geology of the Argyre quadrangle of Mars is dominated by the conspicuous Argyre basin, defined by a rim of rugged mountain blocks that surrounds a nearly circular expanse of plains 800 km across. Of the large (greater than 500 km in diameter) basins identified on Mars, Argyre is the best preserved and probably the youngest. Basins appear to be traps for eolian debris and evidently...

The Aristoteles quadrangle, located on the northeastern periphery of the Imbrium basin on the near side of the Moon, consist of four physiographic provinces: a northern mountainous belt, chiefly of lineated crater rims and other lineated terra; a middle-northern belt covered by mare material of Mare Frigoris; and a southern belt composed of mountainous material of diverse characteristics...

The Bach region encompasses the south polar part of Mercury poleward of lat 65 degrees S. About half of the region was beyond the terminator during the three Mariner 10 encounters and hence not visible. The entire mapped area was covered by near-vertical photography from the second encounter, and the eastern part, from long 15 degrees to about 110 degrees, was covered by oblique...

The Beethoven quadrangle is located in the equatorial region of Mercury, in the center of the imaged area. Most pictures of the quadrangle were obtained at high sun angles as the Mariner 10 spacecraft receded from the planet. Images in the northeastern part of the quadrangle are very poor to unusable. Another difficulty in mapping is the poor match in topographic bases between Beethoven...

Most of the photographs used for geologic mapping were acquired by the departing spacecraft during the first pass (Mercury I). The Mercury II encounter provided no usable images of the map area; two low-oblique photographs suitable for geologic mapping were acquired during the third flyby on March 17, 1975 (Davies and others, 1978, p. 31). No stereoscopic phtographic pairs are available...

The Magellan spacecraft orbited Venus from August 10, 1990, until it plunged into the venusian atmosphere on October 12, 1994. Magellan had the objectives of (1) improving knowledge of the geologic processes, surface properties, and geologic history of Venus by analysis of surface radar characteristics, topography, and morphology and (2) improving knowledge of the geophysics of Venus by...