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تسجيل مستخدم جديدLinking Europas plume activity to tides, tectonics, and liquid water
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Much of the geologic activity preserved on Europas icy surface has been attributed to tidal deformation, mainly due to Europas eccentric orbit. Although the surface is geologically young (30 - 80 Myr), there is little information as to whether tidally-driven surface processes are ongoing. However, a recent detection of water vapor near Europas south pole suggests that it may be geologically active. Initial observations indicated that Europas plume eruptions are time-variable and may be linked to its tidal cycle. Saturns moon, Enceladus, which shares many similar traits with Europa, displays tidally-modulated plume eruptions, which bolstered this interpretation. However, additional observations of Europa at the same time in its orbit failed to yield a plume detection, casting doubt on the tidal control hypothesis. The purpose of this study is to analyze the timing of plume eruptions within the context of Europas tidal cycle to determine whether such a link exists and examine the inferred similarities and differences between plume activity on Europa and Enceladus.
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Physical processing of Europan surface water ice by thermal relaxation, charged particle bombardment, and possible cryovolcanic activity can alter the percentage of the crystalline form of water ice compared to that of the amorphous form of water ice
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