Transcription: Zdenek Okoni, Celestial Gallery, Kalisto. At first glance Kalisto seems quite mundane. With its pockmarked surface and its white circular patches it may even seem a little dull. Yet there is much of interest here. Generally speaking, dark areas are older than bright regions, and Kalisto has an icy surface. As with Ganymede and many other satellites, masses of ice, but the oldest surface has been partly covered by interplanetary dust and so appears dark. The long-term effects of solar radiation can also produce dark regions. Occasionally a meteorite will hit the surface. When this happens, the ...
(.mp4)