Tiny, dust-sized particles in Saturn's rings become much easier to see at
high phase angle -- the angle formed by the Sun, the rings and the
spacecraft. The brightest ring is the F ring; the next feature to the left
is the outer edge of the A ring. Inward of that, and very bright, are the
ringlets in the Encke gap.
Epimetheus (116 kilometers, or 72 miles across) is easy to spot just
right of the outer F ring edge. Janus (181 kilometers, or 113 miles
across), however, is quite a bit harder to make out; it is the dark spot
located directly to the left of Epimetheus, above the gap between the A
and F rings.
Within the space between the A and F rings there are two faint rings seen
previously by the Cassini spacecraft. The inner faint ring (called R/2004
S1) coincides with the orbit of Atlas. The outer one forms the inner
boundary of the orbit of Prometheus.
The narrow G ring is visible above and below the bright F ring.
The image was taken in visible light with the Cassini spacecraft
narrow-angle camera on July 15, 2006 at a distance of approximately 2.7
million kilometers (1.7 million miles) from Epimetheus and 2.8 million
kilometers (1.7 million miles) from Janus. The view was acquired at a
Sun-Epimetheus-spacecraft, or phase, angle of 164 degrees. Image scale is
16 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.