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We propose to obtain high spatial resolution imaging polarimetry of the surface of Europa to localize features in the polarization phase curve which are diagnostic of fresh deposition comma sintering and aging comma allowing identification of regions of recent cryovolcanism and subsurface activity. We will seek a relationship between polarization and global thermal inertia maps comma and between polarization and spectroscopically distinct compositional units. Polarization and thermal inertia probe regolith porosity comma surface transparency comma composition and topography comma while spectroscopically distinct regions relate to absorbing chemical admixtures. The overall global polarization pattern will constrain the systematic ice scattering characteristics. This polarimetric suite of high-resolution HST images comma with its unique emphasis on surface physics comma will complement the wide variety of upcoming observations from major flagship missions JWST comma Europa Clipper comma JUICE and Juno as well as thermal ALMA imaging. With Europa and its global saline ocean at the forefront of strategic planning for NASA and ESA as a target of exceptional astrobiological importance comma it is essential to advance our understanding of the Europa surface to the maximum.本研究拟对木卫二（Europa）表面开展高空间分辨率成像偏振测量，以定位偏振相位曲线中可指示新鲜沉积、烧结与老化过程的特征，进而识别近期冰火山活动与地下活动区域。我们将探寻偏振信号与全球热惯量地图之间的关联，以及偏振信号与光谱特征各异的成分单元之间的联系。偏振测量与热惯量可表征表岩屑孔隙率、表面透明度、成分与地形特征，而光谱特征不同的区域则与吸收性化学掺合物相关。整体全球偏振模式将限定系统性冰散射特性。这套高分辨率哈勃空间望远镜（Hubble Space Telescope, HST）偏振成像数据集，凭借其对表面物理研究的独特侧重，将与多项即将开展的旗舰级探测任务——包括詹姆斯·韦布空间望远镜（James Webb Space Telescope, JWST）、欧罗巴快帆（Europa Clipper）、木星冰月探测器（JUpiter ICy moons Explorer, JUICE）、朱诺号（Juno）以及阿塔卡马大型毫米/亚毫米波阵列（Atacama Large Millimeter/submillimeter Array, ALMA）的热成像观测——形成互补。鉴于木卫二及其全球含盐海洋是美国国家航空航天局（National Aeronautics and Space Administration, NASA）与欧洲空间局（European Space Agency, ESA）战略规划中的前沿天体生物学关键目标，最大限度深化对木卫二表面的认知至关重要。