A Kelvin-Helmholtz instability on Saturn, caused by the interaction between two bands of the planet's atmosphere. Image from the Cassini probe. Caption from NASA's press release: This turbulent boundary between two latitudinal bands in Saturn's atmosphere curls repeatedly along its edge in this Cassini image. This pattern is an example of a Kelvin-Helmholtz instability, which occurs when two fluids of different density flow past each other at different speeds. This type of phenomenon should be fairly common on the gas giant planets given their alternating jets and the different temperatures in their belts and zones. The image was taken with the Cassini spacecraft narrow angle camera on October 9, 2004, at a distance of 5.9 million kilometers (3.7 million miles) from Saturn through a filter sensitive to wavelengths of infrared light centered at 889 nanometers. The image scale is 69 kilometers (43 miles) per pixel.