Jet Propulsion Laboratory, Mail Stop 183-501, 4800 Oak Grove Drive, Pasadena, CA 91109, USA.
Science. 2010 Apr 30;328(5978):605-8. doi: 10.1126/science.1186785. Epub 2010 Apr 8.
The questions of whether Venus is geologically active and how the planet has resurfaced over the past billion years have major implications for interior dynamics and climate change. Nine "hotspots"--areas analogous to Hawaii, with volcanism, broad topographic rises, and large positive gravity anomalies suggesting mantle plumes at depth--have been identified as possibly active. This study used variations in the thermal emissivity of the surface observed by the Visible and Infrared Thermal Imaging Spectrometer on the European Space Agency's Venus Express spacecraft to identify compositional differences in lava flows at three hotspots. The anomalies are interpreted as a lack of surface weathering. We estimate the flows to be younger than 2.5 million years and probably much younger, about 250,000 years or less, indicating that Venus is actively resurfacing.
金星是否具有地质活动性，以及在过去十亿年中行星是如何重新形成表面的，这些问题对内部动力学和气候变化有重大影响。已经确定了九个“热点”——类似于夏威夷的区域，具有火山作用、广泛的地形隆起和大的正重力异常，表明深部存在地幔柱——可能具有活动性。这项研究利用欧洲航天局金星快车号航天器上的可见和红外热成像光谱仪观测到的表面热发射率变化，在三个热点地区识别出熔岩流的成分差异。这些异常被解释为缺乏表面风化。我们估计这些熔岩流的年龄小于 250 万年，可能更年轻，约为 25 万年或更短，这表明金星正在积极重新形成表面。
