Rings and satellites
◎planetary rings
◎roche limit以內的小物體都會受到行星作用
◎Jupiter:Discovery image from Voyager、gossamar ring
◎Saturnian rings from Cassini:Enceladus、Mimas
◎Christiaan Huygens’Saturn ring model、Cassini division
◎Radial variation of Optical depth
◎density waves:keeler gap
◎Sheperding satellites
◎Galilean Satellites:Io、Europa、 Ganymede、 Callisto