January 31, 2007
Two bright vortices roll across the cloud-lined face of Saturn, where winds howl at high speeds never experienced on Earth.
This view was acquired at about the same time as Cloud Lanes but the planet appears darker here. This is because the spectral filter used to acquire this image looks at a part of the spectrum where methane absorption in Saturn's atmosphere is stronger. Thus, photons do not penetrate as deep into the Saturn atmosphere as they do at the wavelengths observed in Cloud Lanes. Since more photons are absorbed here, the planet looks darker.
The icy particles composing the rings do not contain methane, and therefore appear bright relative to Saturn.
The image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 862 nanometers. The view was obtained using the Cassini spacecraft wide-angle camera on Dec. 13, 2006 at a distance of approximately 775,000 kilometers (481,000 miles) from Saturn. Image scale is 43 kilometers (27 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
Credit: NASA/JPL/Space Science Institute