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Bruce Murray Space Image Library

Titan, Dione, rings, Prometheus

Titan, Dione, rings, Prometheus
Titan, Dione, rings, Prometheus Cassini captured the three images for this approximately true color composite on 18 October 2010. While Cassini studied Titan, the mid-sized icy moon Dione wandered through the field of view, while Prometheus sat atop the F ring at upper left. NASA / JPL-Caltech / SSI / color composite by Emily Lakdawalla
A Cassini color image without alignment
A Cassini color image without alignment Three images taken through red, green, and blue filters on October 18, 2010 were combined into a color composite without any alignment of the individual images. The most obvious problem is with Dione, which clearly moved between red, green, and blue filters, but if you look at upper left you can see the tiny potato shape of Prometheus showing up in only red and green filters and absent entirely from the blue filter image. Less obvious are color channel misalignments among the rings and on Titan; the blue channel is shifted several pixels upward with respect to the red and green channels, resulting in a blue halo above Titan and the rings and a yellow and green halo below them.Image: NASA / JPL-Caltech / SSI / color composite by Emily Lakdawalla