Continuing on its dedicated Saturnian mission, the Cassini spacecraft has returned further marvelous images of this pair of the ringed planet’s moons, Dione and Rhea. Clicking on each image will take you directly to the accompanying press releases. All images and captions courtesy of NASA/JPL/Space Science Institute.

The leading hemisphere of Dione displays subtle variations in color across its surface in this false color view.

To create this view, ultraviolet, green and infrared images were combined into a single black and white picture that isolates and maps regional color differences. This “color map” was then superposed over a clear-filter image. The origin of the color differences is not yet understood, but may be caused by subtle differences in the surface composition or the sizes of grains making up the icy soil.

Terrain visible here is on the moon’s leading hemisphere. North on Dione (1,126 kilometers, or 700 miles across) is up and rotated 17 degrees to the right.

The image [along with its above counterpart] was taken with the Cassini spacecraft narrow-angle camera on Dec. 24, 2005 at a distance of approximately 597,000 kilometers (371,000 miles) from Dione and at a Sun-Dione-spacecraft, or phase, angle of 21 degrees. Image scale is 4 kilometers (2 miles) per pixel.

This close view of Rhea prominently shows two large impact basins on the ancient and battered moon. The great age of these basins is suggested by the large number of smaller craters that are overprinted within them.

Ejecta from the bright, relatively young crater seen in PIA07609 spreads from the eastern limb. Terrain visible in this view is on the side of Rhea (1,528 kilometers, or 949 miles across) that faces away from Saturn. North on Rhea is up and tilted 30 degrees to the left.

This enhanced color view was created by combining images taken using filters sensitive to ultraviolet, visible green and infrared light. The images were taken with the Cassini spacecraft narrow-angle camera on Dec. 23, 2005, at a distance of approximately 341,000 kilometers (212,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 42 degrees. The image scale is 2 kilometers (1 mile) per pixel.

The image was taken with the Cassini spacecraft narrow-angle camera on Dec. 23, 2005 using a spectral filter sensitive to wavelengths of infrared light centered at 930 nanometers.

Don’t forget to head outside and take advantage of viewing Saturn at opposition — with enough aperture you should be able to make out both of the above moons in addition to their other orbiting neighbors. Sky & Telescope’s online edition offers this neat little java utility you can use to locate Saturn’s largest five moons (under good conditions, I’ve viewed as many as eight as eight of the satellites through my dobsonian). Also see S&T’s Saturn observing guide and this week’s Sky at a Glance.