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. |
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