这种双卫效果受益于离摄像机较近的狄俄涅（土卫四）和离摄像机较远但是比前者稍大些的瑞亚（土卫五）一致的反射率。
The double-moon effect is aided by the matching reflectivity of Dione (top), which is closer to the camera, and Rhea, which is farther away but slightly larger than Dione.
狄俄涅“下部”边缘上巨大而模糊的火山口关键性的校直完成了这个天文学假象。
The strategic alignment of a large, faint crater at the "bottom" edge of Dione completes the astronomical illusion.
土卫四(狄俄涅)，右边那颗，直径小于土卫六的四分之一，没有明显的大气层。
Dione, on the right, has less than a quarter of Titan's diameter and has no significant atmosphere.
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