Feb 11, 2014: Saturn's Colorful Aurora - While the curtain-like auroras we see at Earth are green at the bottom and red at the top, NASA's Cassini spacecraft has shown us similar curtain-like auroras at Saturn that are red at the bottom and purple at the top to the human eye. (Press release can be found here.)
December 18, 2012
After more than eight years in orbit and just in time for the holidays, Cassini has delivered another awe-inspiring backlit view of Saturn and its rings.
On Oct. 17, 2012, during its 174th orbit around the gas giant, the spacecraft was deliberately positioned within Saturn's shadow, a perfect location from which to look back at Saturn in the direction of the sun and take a backlit view of the rings and the dark side of the planet. Looking at a plantary body illuminated by the sun from behind is a geometry referred to by planetary scientists as "high solar phase;" near the center of the body's shadow is the highest phase possible. This is a very coveted viewing position as it can reveal details about the target, in this particular case both the planet's atmosphere and rings, that cannot be seen at lower solar phase.
The last time Cassini had such an unusual perspective on Saturn and its rings, at sufficient distance and with sufficient time to take a full mosaic of images of the entire system, occurred in September 2006 when it captured a mosaic of images, processed to look like natural color, entitled "In Saturn's Shadow-The Pale Blue Dot". In that mosaic, planet Earth put in a special appearance, making "In Saturn's Shadow" our most popular Cassini image of all time.
The mosaic we are releasing today does not contain Earth: Along with the sun, our planet is hidden behind Saturn. However, it was taken when Cassini was closer to Saturn and therefore shows more detail in the rings than the one from six years ago. It also is displayed as it truly is, in false-color ... leaving a rather eerie and surreal impression on the viewer.
Of all the many glorious images we have received from Saturn, none are more strikingly unusual than those we have taken from Saturn's shadow. They unveil a rare splendor seldom seen anywhere else in our solar system.
This one is our special gift to you, the people of the world, in this holiday season that brings to a close the year 2012. We fervently hope it serves as a reminder that we humans, though troubled and warlike, are also the dreamers, thinkers, and explorers inhabiting one achingly beautiful planet, yearning for the sublime, and capable of the magnificent. We hope it reminds you to protect our planet with all your might and cherish the life it so naturally sustains.
From all of us on Cassini, the happiest of holidays to everyone.
Carolyn Porco Cassini Imaging Team Leader Director, CICLOPS Boulder, CO