Mimas in Blue

Mimas, a tiny icy moon of Saturn 398 kilometers across (247 miles), is seen dwarfed against the azure backdrop of Saturn's northern latitudes in this true color view. The dark long lines seen on the atmosphere are shadows cast by Saturn’s rings. A few visible large craters give Mimas a dimpled appearance.

The image was taken by the Cassini spacecraft's narrow angle camera on January 18, 2005, when it was approximately 1.4 million kilometers (870,000 miles) from Saturn. The resolution is 8.5 kilometers (5.3 miles) per pixel on Saturn and 7.5 kilometers (4.7 miles) per pixel on Mimas.

Saturn’s northern hemisphere was relatively cloud-free at that time and so rays from the Sun took a longer path through the atmosphere. This resulted in the sunlight being scattered at shorter (bluer) wavelengths and gave the northernmost latitudes their bluish hues at visible wavelengths.

The image was taken using infrared (930 nanometers), green (568 nanometers) and ultraviolet (338 nanometers) spectral filters, which were then combined. The colors were then adjusted to match what the scene would look like in natural color.