Phases of Rhea
Phases of Rhea The angle from the Sun, to a moon, to the observer is called "phase angle." This montage shows Saturn's moon Rhea as seen by Cassini through a clear filter at a variety of phase angles. The images have been resized to a constant pixel scale and rotated so that the terminator is up-and-down; the images sample a variety of latitudes and longitudes. NASA / JPL-Caltech / SSI / montage by Emily Lakdawalla

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