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The Kuiper quadrangle, located in a heavily cratered region of Mercury, includes the young, 55-km-diameter crater Kuiper (11° S., 31.5° ), which has the highest albedo recorded on the planet,〔Hapke, Bruce, Danielson, G. E., Jr., Klaasen, Kenneth, and Wilson, Lionel, 1975, Photometric observations of Mercury from Mariner 10: Journal of Geophysical Research, v. 80, no. 17, p. 2431–2443.〕 and the small crater Hun Kal (0.6° S., 20.0° ), which is the principal reference point for Mercurian longitude (Davies and Batson, 1975). Impact craters and basins, their numerous secondary craters, and heavily to lightly cratered plains are the characteristic landforms of the region. At least six multiringed basins ranging from 150 km to 440 km in diameter are present. Inasmuch as multiringed basins occur widely on that part of Mercury photographed by Mariner 10, as well as on the Moon and Mars, they offer a potentially valuable basis for comparison between these planetary bodies. == Mariner 10 photography == Basic information about the planetary surface of the Kuiper quadrangle is provided by three sequences of high-quality photographs designated Mercury I, II, and III, obtained during the incoming phases of three encounters of the Mariner 10 spacecraft with Mercury. Mercury I includes 75 whole-frame photographs of the Kuiper quadrangle; Mercury II, 13 whole-frame photographs; and Mercury III, 70 quarter-frame photographs. The photographs include 19 stereopairs in the southern part of the quadrangle.〔For examples of Mariner 10 photography, see 〕 The most distant of the photographs was taken at an altitude of 89,879 km, the closest at an altitude of 7,546 km. Resolution, therefore, varies widely but ranges from about 1.5 to 2.0 km over most of the area. A wide range (more than 50 deg) of both viewing and solar illumination angles precludes a high degree of mapping consistency. The easternmost 10° of the quadrangle is beyond the evening terminator. A low angle of solar illumination and a high viewing angle make possible discrimination of topographic detail near the terminator. Higher angles of solar illumination and lower viewing angles make it increasingly difficult to discern topographic variations to the west. Many geologic units cannot be specifically identified because of unfavorable viewing geometry west of approximately 55 deg. Thus, mapping reliability decreases westward. Mapping methods and principles are adapted from those developed for lunar photogeologic mapping (Wilhelms, 1970, 1972; Wilhelms and McCauley, 1971). Map units are distinguished on the basis of topography, texture, and albedo and are ranked in relative age on the basis of superposition and transection relations, density of superposed craters, and sharpness of topography. Because of the lack of a widespread, easily identifiable stratigraphic datum on this part of Mercury, a morphologic classification of crater and basin materials was the basis for determining relative ages of many materials. A photomosaic map of the best available photographs aided greatly in geologic interpretation and mapping. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kuiper quadrangle」の詳細全文を読む スポンサード リンク
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