PIA06603: Little Moons

Little Moons


The irregularly-shaped moon Janus (181 kilometers, or 113 miles across) and the small ring moon Atlas (32 kilometers, 20 miles across) had just emerged from the darkness of Saturn's shadow when Cassini caught this view of the two moons.

Saturn's bright A ring is largely overexposed in this view, but several other ring details are nicely visible. The image shows two bright regions within the B ring (at right), ringlets of material within the dark, narrow Encke Gap and kinks in the F ring.

North on Saturn is tilted toward upper left. This view is from Cassini's vantage point beneath the ring plane. It is notable that, as Saturn orbits the Sun, its shadow has been steadily creeping farther out along the ring plane and now extends beyond the F ring.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 26, 2005, at a distance of approximately 3.2 million kilometers (2 million miles) from Janus and at a Sun-Janus-spacecraft, or phase, angle of 81 degrees. The image scale is 19 kilometers (12 miles) per pixel.

Background Info:

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 and the Cassini imaging team home page, http://ciclops.org .

Cataloging Keywords:

Name Value Additional Values
Target Janus A Ring, Atlas, Encke Gap, Saturn, Saturn Rings
System Saturn
Target Type Satellite Gap, Planet, Ring
Mission Cassini-Huygens
Instrument Host Cassini Orbiter
Host Type Orbiter
Instrument Imaging Science Subsystem (ISS)
Detector Narrow Angle Camera
Extra Keywords Grayscale, Shadow, Visual
Acquisition Date
Release Date 2005-03-11
Date in Caption 2005-01-26
Image Credit NASA/JPL/Space Science Institute
Source photojournal.jpl.nasa.gov/catalog/PIA06603
Identifier PIA06603