Scientists celebrated this week after finally seeing ghostly spokes in Saturn's rings. These spokes were first discovered by NASA's Voyager spacecraft 25 years ago, but so far, Cassini had failed to image them. These spokes are about 2,500 km long and 100 km wide (2,200 miles by 60 miles), and are believed to be created by Saturn's magnetic field interacting with the rings. Scientists thought that the visibility of the spokes depended on the angle of Saturn's rings to the Sun; the less sunlight, the easier it should be to spot the spokes.