This movie of Saturn's southern hemisphere taken by the Cassini spacecraft
cameras shows a banded appearance due to winds, as well as dark cyclonic
ovals.
The movie is comprised of 45 frames captured between February 6 and March
30, 2004, as Cassini coasted toward Saturn. The images were projected
onto a rectangular longitude system to make a cylindrical map, with one
map for each rotation of the planet that was captured by the cameras.
These cylindrical maps (shown here also in movie form) were then
projected back onto a globe-shaped Saturn.
This view of Saturn is similar to those seen in movies made from Cassini's
encounter with Jupiter, except that in this case only the dark ovals are
visible, not the background jets. The jets are there, but their features
are much more muted. It is not yet clear whether all the ovals visible
here are cyclonic, meaning that their winds flow in a counter-clockwise
direction. However, the ovals resemble the cyclonic ovals Cassini spied
on Jupiter. A few of the ovals seem to change their apparent direction of
travel, from westward to eastward, as they change their latitude. This
fascinating behavior was also noted by Cassini imaging scientists with
ovals on Jupiter. Two mergers of ovals are captured in this sequence, one
of which was reported previously (see PIA05386).
The images in this movie were taken with the narrow angle camera using a
spectral filter centered at 750 nanometers, and from distances ranging
from 70.8 million kilometers (44 million miles) to 46.3 million kilometers
(28.8 million miles) from Saturn. The image scale ranges from 425
kilometers (264 miles) to 278 kilometers (173 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 Cassini-Huygens mission for NASA's Office of Space Science,
Washington, D.C. The Cassini orbiter and its two onboard cameras, were
designed, developed and assembled at JPL. The imaging team is based at
the Space Science Institute, Boulder, Colo.
For more information, about the Cassini-Huygens mission visit,
http://saturn.jpl.nasa.gov and the Cassini imaging team home page,
http://ciclops.org.