Gaseous Saturn rotates quickly -- once every approximately 10.8 hours --
and its horizontal cloud bands rotate at different rates relative to each
other. These conditions can cause turbulent features in the atmosphere to
become greatly stretched and sheared, creating the beautiful patterns that
the Cassini spacecraft observes. This turbulence and shear is particularly
notable at those boundaries where the different bands slide past each
other.
Vortices like the one seen here are long-lived dynamical features that are
part of the general circulation of Saturn's atmosphere. They are
counterparts to the east-west flowing jets and can last for months or
years. They probably grow by merging with other vortices until a few
dominate a particular shear zone between two jets.
This image was taken in polarized infrared light with the Cassini
spacecraft narrow-angle camera on March 7, 2006, at a distance of
approximately 2.9 million kilometers (1.8 million miles) from Saturn. The
image scale is 17 kilometers (10 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.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging team
homepage is at http://ciclops.org.
