The factors contributing to the initial selection of a dune site near the Selk impact structure on Titan as the first landing site for the Dragonfly mission are described. These include arrival geometry and aerodynamic/aerothermodynamic considerations, illumination, and Earth visibility, as well as the likely presence of exposed deposits of water-rich material, potentially including materials where molten ice has interacted with organics. Cassini observations of Selk are summarized and interpreted: near-infrared reflectance and microwave emission data indicate water-rich materials in and around the crater. Radar topography data shows the rim of Selk to have slopes on multi-km scales reaching only ∼2 degrees, an order of magnitude shallower than early photoclinometric estimates.

描述了导致最初选择泰坦上 Selk 撞击结构附近的沙丘地点作为蜻蜓任务的第一个着陆点的因素。其中包括到达几何和空气动力学/空气热力学考虑因素、照明和地球能见度，以及可能存在暴露的富含水物质的沉积物，可能包括熔冰与有机物相互作用的物质。卡西尼号对塞尔克的观测进行了总结和解释：近红外反射率和微波发射数据表明陨石坑内和周围富含水的物质。雷达地形数据显示，塞尔克边缘的坡度在数公里范围内仅达到约 2 度，比早期的光度测量估计要浅一个数量级。