As Cassini nears its rendezvous with Saturn, new detail in the banded
clouds of the planet's atmosphere are becoming visible.
Cassini began the journey to the ringed world of Saturn nearly seven
years ago and is now less than two months away from orbit insertion on
June 30. Cassini’s narrow-angle camera took this image on April 16, 2004,
when the spacecraft was 38.5 million kilometers (23.9 million miles) from
Saturn.
Dark regions are generally areas free of high clouds, and bright areas
are places with high, thick clouds which shield the view of the darker
areas below. A dark spot is visible at the south pole, which is remarkable
to scientists because it is so small and centered. The spot could be
affected by Saturn's magnetic field, which is nearly aligned with the
planet's rotation axis, unlike the magnetic fields of Jupiter and Earth.
From south to north, other notable features are the two white spots just
above the dark spot toward the right, and the large dark oblong-shaped
feature that extends across the middle. The darker band beneath the
oblong-shaped feature has begun to show a lacy pattern of lighter-colored,
high altitude clouds, indicative of turbulent atmospheric conditions.
The cloud bands move at different speeds, and their irregularities may
be due to either the different motions between them or to disturbances
below the visible cloud layer. Such disturbances might be powered by the
planet's internal heat; Saturn radiates more energy than it receives from
the Sun.
The moon Mimas (396 kilometers, 245 miles across) is visible to the
left of the south pole. Saturn currently has 31 known moons. Since launch,
13 new moons have been discovered by ground-based telescopes. Cassini will
get a closer look and may discover new moons, perhaps embedded within the
planet’s magnificent rings.
This image was taken using a filter sensitive to light near 727
nanometers, one of the near-infrared absorption bands of methane gas,
which is one of the ingredients in Saturn's atmosphere. The image scale is
approximately 231 kilometers (144 miles) per pixel. Contrast has been
enhanced to aid visibility of features in the atmosphere.
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.
