关于这张图
This enhanced-color mosaic of Saturn's icy moon Tethys shows a range of features on the moon's trailing hemisphere. Tethys is tidally locked to Saturn, so the trailing hemisphere is the side of the moon that always faces opposite its direction of motion as it orbits the planet. Images taken using clear, green, infrared and ultraviolet spectral filters were combined to create the view, which highlights subtle color differences across Tethys' surface at wavelengths not visible to human eyes. The moon's surface is fairly uniform in natural color. The color of the surface changes conspicuously a…