土卫六中纬度云层的演变。

The evolution of Titan's mid-latitude clouds.

作者信息

Griffith C A, Penteado P, Baines K, Drossart P, Barnes J, Bellucci G, Bibring J, Brown R, Buratti B, Capaccioni F, Cerroni P, Clark R, Combes M, Coradini A, Cruikshank D, Formisano V, Jaumann R, Langevin Y, Matson D, McCord T, Mennella V, Nelson R, Nicholson P, Sicardy B, Sotin C, Soderblom L A, Kursinski R

机构信息

Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.

出版信息

Science. 2005 Oct 21;310(5747):474-7. doi: 10.1126/science.1117702.

DOI:10.1126/science.1117702

PMID:16239472

Abstract

Spectra from Cassini's Visual and Infrared Mapping Spectrometer reveal that the horizontal structure, height, and optical depth of Titan's clouds are highly dynamic. Vigorous cloud centers are seen to rise from the middle to the upper troposphere within 30 minutes and dissipate within the next hour. Their development indicates that Titan's clouds evolve convectively; dissipate through rain; and, over the next several hours, waft downwind to achieve their great longitude extents. These and other characteristics suggest that temperate clouds originate from circulation-induced convergence, in addition to a forcing at the surface associated with Saturn's tides, geology, and/or surface composition.

摘要

卡西尼号的可见光和红外绘图光谱仪获取的光谱显示，土卫六云层的水平结构、高度和光学厚度具有高度动态性。观测到活跃的云团中心在30分钟内从对流层中部上升到上部，并在接下来的一小时内消散。它们的形成表明土卫六的云层通过对流演化；通过降雨消散；并且在接下来的几个小时里，随风向下漂移，从而在经度上延伸很远。这些以及其他特征表明，温带云层除了源于与土星潮汐、地质和/或表面成分相关的地表强迫作用外，还源于环流引起的辐合。