Lorenz Ralph
Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.
Science. 2003 Oct 17;302(5644):403-4. doi: 10.1126/science.1090464. Epub 2003 Oct 2.
It has long been known that Saturn's largest moon, Titan, has a thick nitrogen atmosphere, which obscures the underlying surface. In his Perspective, Lorenz highlights the report by Campbell et al., who have used the giant Arecibo and Green Bank radio telescopes as a radar to probe Titan's hidden surface. The surface appears to be distinct from those of the icy satellites of Jupiter, in both brightness and polarization. The new data show sharp spikes in the reflected microwave spectrum, indicating large, smooth areas of radar-dark material. These features suggest the widespread existence of lakes or seas of liquid hydrocarbons on Titan.
长期以来，人们一直知道土星最大的卫星土卫六拥有浓厚的氮气大气层，这使得其下层表面难以被观测到。洛伦兹在他的《观点》中强调了坎贝尔等人的报告，他们使用巨大的阿雷西博和格林班克射电望远镜作为雷达来探测土卫六隐藏的表面。在亮度和偏振方面，土卫六的表面似乎与木星的冰卫星不同。新数据显示反射微波光谱中有尖锐的峰值，表明存在大面积的雷达暗物质平滑区域。这些特征表明土卫六上广泛存在液态碳氢化合物湖泊或海洋。
