PIA11568: Shadow Crosses a Gap
- Original Caption Released with Image:
The shadow of the moon Janus crosses the Encke Gap as it strikes the plane
of Saturn's rings in this image taken as the planet approached its August
Janus (179 kilometers, or 111 miles across) is not shown here, but the
moon's shadow appears on the A ring. Prometheus (86 kilometers, or 53
miles across) can be seen near the bottom of the image as it orbits in the
Roche Division between the A ring and the thin F ring.
The novel illumination geometry created around the time of Saturn's August
2009 equinox allows moons orbiting in or near the plane of Saturn's
equatorial rings to cast shadows onto 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. To learn more about this special time
and to see movies of moons' shadows moving across the rings, see PIA11651
This view looks toward the sunlit side of the rings from about 41 degrees
below the ringplane.
The image was taken in visible red light with the Cassini spacecraft
wide-angle camera on June 9, 2009. The view was obtained at a distance of
approximately 575,000 kilometers (357,000 miles) from Saturn and at a
Sun-Saturn-spacecraft, or phase, angle of 76 degrees. Image scale is 31
kilometers (19 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/. 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 --