Cassini's confirmation that a small moon orbits within the Keeler gap in
Saturn's rings is made all the more exciting by this image, in which the
disk of the 7 kilometer-wide body (4-miles) is resolved for the first
time.
The new body, provisionally named S/2005 S1, was first seen in a
time-lapse sequence of images taken on May 1, 2005, as Cassini began its
climb to higher elevations in orbit around Saturn (see PIA06238 for the
movie). This view was acquired one day after the discovery sequence of
images and has allowed scientists to measure the moon's size and
brightness.
The Keeler gap edges also bear similarities to the scalloped edges of
the 322-kilometer-wide (200-mile) Encke gap, where Pan resides. From the
size of the waves seen in the Encke gap, imaging scientists were able to
estimate the mass of Pan. They expect to do the same eventually with this
new moon.
This image was obtained with the Cassini spacecraft narrow-angle camera
on May 2, 2005, at a distance of about 594,000 kilometers (369,000 miles)
from Saturn. Cassini was about 525,000 kilometers (326,000 miles) above
the ringplane when the image was taken. Resolution in the original image
was 3 kilometers (2 miles) per pixel. The image has been magnified by a
factor of two, and contrast has been enhanced, to aid visibility of the
small moonlet.
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 team is based at the Space Science
Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov.
For additional images visit the Cassini imaging team homepage http://ciclops.org.