NASA's Cassini spacecraft will fly by Saturn's moon Enceladus this weekend for a last peek at the intriguing "tiger stripes" before winter darkness blankets the area for several years.
Massive, bright clouds of tiny ice particles hover above the darkened rings of Saturn in an image captured by the Cassini spacecraft on Sept. 22, 2009, around the time of Saturn's equinox.
A Cassini scientist explains the flickering "northern lights" high above Saturn, shown for the first time in a visible-light movie.
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After a 15-year wait, equinox arrived at Saturn and Cassini was there to witness the spectacle of light and shadow.
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