... The storm (top) was actually spotted last month by amateur astronomers as it rotated across Saturn's day side and spans about 3,500 kilometers. An Unusually Smooth Surface on Saturns Telesto . ... Why is Saturn's small moon Telesto so smooth? Possibly Telesto is covered with a type of granular icy material similar to that suspected of covering Pandora, another of Saturn's small moon's. If so, Telesto might be more like a pile of rubble than a solid body. ... The Color of the Moon . ...