Calypso Calypso, only 34 x 22 x 22 kilometers in diameter, occupies the L4 Lagrangian point in Tethys' orbit -- it sits in a point 60 degrees ahead of Tethys. NASA / JPL-Caltech / SSI / color composite by Emily Lakdawalla

Cassini passed within 22,000 kilometers of the moon on February 13, 2010, for the best look yet at its smooth, icy surface. This view is a color composite from Cassini's raw images, red, green, and blue frames overlaid on a stacked composite of red, green, blue, and clear images. (Stacking mostly serves to decrease the artifacts caused by the JPEG format of the raw images.)

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