A Long Baseline Investigation of Clouds, Haze and Methane Distributions on Titan

AST-0909137 Young该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。土星最大的卫星土卫六可能是太阳系中唯一一个正在经历降水，液体和风成侵蚀以及烟雾状薄雾形成和消散的熟悉大气过程的天体。 该项目将解决有关土卫六的几个悬而未决的问题，例如大气中甲烷的来源（它应该存在数千万年而不被补充），为什么云会在某些特定的时间出现在特定的纬度范围内，以及烟雾如何在南北半球之间迁移。该项目有五个目标：1）调查是否可以从土卫六的地图上检测到局部的甲烷来源; 2）确定甲烷凝结条件随时间、纬度和高度的变化特征; 3）将泰坦区域大气模拟系统（TRAMS）的预测与对流云的高分辨率图像序列进行比较; 4）调查是否存在“早晨增亮”现象，即东/西边缘亮度的日不对称性; 5）绘制1996年至2007年烟霞的纬度和高度分布图。 该研究对土卫六的大气层及其甲烷云的性质进行了限制，这些甲烷云来自卡西尼号航天器数据，哈勃太空望远镜观测和地面凯克图像，部分用TRAMS进行了解释。 分析将包括构建甲烷和霾廓线的三维半球形地图，根据卡西尼复合红外光谱仪获得的光谱确定温度廓线，并研究卡西尼成像科学子系统图像序列中的云，以确定对流云成分的规模和寿命。土卫六是一个重要的实验室，用于研究降水、侵蚀和烟雾状薄雾的性质等熟悉的过程。 该项目还将支持爱达荷州大学的暑期本科生，他们将协助并接受天文数据处理方面的培训。 这项工作支持了马里兰州大学的一名博士后学者。

AST-0909137YoungThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Saturn's largest moon, Titan, is perhaps the only other body in the solar system currently experiencing the familiar atmospheric processes of precipitation, liquid and aeolian erosion, and the formation and dissipation of smog-like haze. This project will resolve several outstanding questions about Titan, such as the source of the atmospheric methane (which should survive for tens of millions of years without being replenished), why clouds appear over specific latitude ranges at certain times, and how the haze migrates between north and south hemispheres.The project has five goals: 1) investigate whether localized sources of methane can be detected from maps of Titan; 2) characterize the conditions for methane condensation as a function of time, latitude and altitude; 3) compare the predictions of the Titan Regional Atmospheric Modeling System (TRAMS) with high-resolution image sequences of convective clouds; 4) investigate if there is such a phenomenon as "morning brightening", a diurnal asymmetry in the east/west limb brightnesses; 5) map the latitudinal and height distributions of haze from 1996 through 2007. The study applies constraints on the properties of Titan's atmosphere and its methane clouds which come from Cassini Spacecraft data, Hubble Space Telescope observations, and ground-based Keck images, interpreted in part with TRAMS. The analysis will include the construction of three-dimensional hemispherical maps of methane and haze profiles, the determination of temperature profiles from spectra obtained with the Cassini Composite Infrared Spectrometer, and a study of clouds in Cassini Imaging Science Subsystem image sequences to determine the scale and lifetime of convective cloud components.Because similar processes are operating on Earth, Titan is an important laboratory for investigating familiar processes like precipitation, erosion, and the properties of smog-like hazes. The project will also support summer undergraduate students at the University of Idaho who will assist and be trained in astronomical data processing. The work supports an additional postdoctoral scholar at the University of Maryland.