Вісник Астрономічної школи (Oct 2011)
Features of morphology and geology of surface of Jupiter satellite Europe
Abstract
Comparison of large-scale images of “Vojager-2” and “Galileo” did not find out no noticeable changes on the surface of Europe. But “Galileo” images of Europe with a high spatial resolution was changed our picture of character and nature of its surface. A surface is an icy shell, covered by cracks and by ice-drifts. Under a comparatively thin shell, possibly, there is an ocean of liquid water in to a few ten of kilometers depth. Very small amount of shock craters specifies on relative youth of surface of Europe and, possibly, on its geological activity and now. The basic geological features of satellite are selected taking into account likeness of form, structure, color, illuminations etc. of Europe surfaces and other known types of surface: large plains regions, areas of cracks (lines, bands) and mountain backbones (linea, lineaes), areas with chaotic relief (chaos, chaoses), craters and cycloid cracks (flexus). Presumably, global network of lines – it caused by tectonic processes in icy shell cracks, after filled the frozen dark matter of orange–red color. Correlation of stratum features with albedo allows to suppose that its young areas, which were less changed by subsequent endogenous and exogenous processes which would clean them, have less albedo. Classification of craters is based on the clearness of scopes of the thrown out breeds. Tracks of shots can be seen on the presence of concentric features; some have well visible edges and shock texture; some have rays. On the Europe surface 41 craters with diameters a 2–50 km are found. In 2000 was found out a large crater which can be the result of collision of asteroid with Europe in the past. Size of external structure of Tayr object (diameter – 149 km) far more than size of its crater. This morphological detail appeared so original, that for it (and yet for 2–3 to it similar) it was necessary to offer the special name: large circular structures. If to examine satellite on the whole, to our opinion, it is necessary to talk about another shock very large circular structure occupying practically all of Europe hemisphere with a center with the co-ordinates of 20S, 203W.
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