PIA11613: Post-Equinox Color
- Original Caption Released with Image:
The Cassini spacecraft captured this natural color view of Saturn almost a
month after the planet's August 2009 equinox. The shadow cast on the
planet by the rings remains narrow.
Spokes are visible on the B ring. To learn more about these ghostly radial
structures, see PIA11144.
Mimas (396 kilometers, or 246 miles across) can be seen in the lower left.
Mimas and the rings have been brightened relative to the planet to
The novel illumination geometry that accompanies equinox lowers the sun's
angle to the ringplane, significantly darkens the rings, and causes
out-of-plane structures to look anomalously bright and cast shadows across
the rings. These scenes are possible only during the few months before and
after Saturn's equinox, which occurs only once in about 15 Earth years.
Before and after equinox, Cassini's cameras have spotted not only the
predictable shadows of some of Saturn's moons (see PIA11657), but also
the shadows of newly revealed vertical structures in the rings themselves
This view looks toward the northern, sunlit side of the rings from about
10 degrees above the ringplane.
The red, green and blue images that were mosaicked together to create this
view were obtained with the Cassini spacecraft wide-angle camera on Sept.
4, 2009. The view was obtained at a distance of approximately 2.7 million
kilometers (1.7 million miles) from Saturn and at a Sun-Saturn-spacecraft,
or phase, angle of 92 degrees. Image scale is 156 kilometers (97 miles)
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/. The Cassini imaging team
homepage is at http://ciclops.org.
- Image Credit:
NASA/JPL/Space Science Institute
Image Addition Date:
Image and caption provided by the Planetary Photojournal --