（4）灶神星的第一个盘分辨光谱
First disk-resolved spectroscopy of (4) Vesta
摘要：
灶神星，第二大的主带小行星，将是第一个被探索在2011年由美国宇航局的黎明任务。这是一个干燥的，可能是分化的身体与光谱表明，它已被玄武岩熔岩流重新浮出水面，与月海没有太大的不同。在这里，我们提出了第一个磁盘分辨光谱观测的小行星从地面。我们用ESO-VLT自适应光学装备的积分场近红外光谱仪SINFONI观测了（4）灶神星，作为其科学验证活动的一部分。灶神星表面的最高空间分辨率约为90公里，是在2004年10月视宁度极佳（0.5”）的情况下获得的。我们观察到整个灶神星表面的光谱变化，可以解释为辉石成分的变化，或表面老化的影响。我们比较灶神星的2微米吸收带的howardite-eucrite-diogenite（HED）陨石被认为是来自灶神星，并建立特定的区域和HED子类之间的特定联系。整体组成被发现是大多数与howardite陨石兼容，虽然一个小区域约180度。东经度可以归因于一个富含闪长岩的地方。最后，我们集中我们的光谱分析的特点，灶神星的亮区和暗区所看到的哈勃太空望远镜的可见光和近红外图像。
英文摘要：
Vesta, the second largest Main Belt asteroid, will be the first to be explored in 2011 by NASA's Dawn mission. It is a dry, likely differentiated body with spectrum suggesting that is has been resurfaced by basaltic lava flows, not too different from the lunar maria. Here we present the first disk-resolved spectroscopic observations of an asteroid from the ground. We observed (4) Vesta with the ESO-VLT adaptive optics equipped integral-field near-infrared spectrograph SINFONI, as part of its science verification campaign. The highest spatial resolution of ~90 km on Vesta's surface was obtained during excellent seeing conditions (0.5") in October 2004. We observe spectral variations across Vesta's surface that can be interpreted as variations of either the pyroxene composition, or the effect of surface aging. We compare Vesta's 2 micron absorption band to that of howardite-eucrite-diogenite (HED) meteorites that are thought to originate from Vesta, and establish particular links between specific regions and HED subclasses. The overallcomposition is found to be mostly compatible with howardite meteorites, although a small area around 180 deg. East longitude could be attributed to a diogenite-rich spot. We finally focus our spectral analysis on the characteristics of Vesta's bright and dark regions as seen from Hubble Space Telescope's visible and Keck-II's near-infrared images.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
