2005 Calendar: Nature's Canvas Poster

In a splendid portrait created by light and gravity, lonely Mimas is seen against the cool, blue-streaked backdrop of Saturn’s northern hemisphere. Delicate shadows cast by the rings arc gracefully across the planet, fading into darkness on Saturn’s night side. The part of the atmosphere seen here appears darker and more bluish than the warm brown and gold hues seen in Cassini images of the southern hemisphere, due to preferential scattering of blue wavelengths by the cloud-free upper atmosphere. The bright blue swath near Mimas (398 kilometres, 247 miles across) is created by sunlight passing through the Cassini division (4,800 kilometres, or 2,980 miles wide). (The rightmost part of this distinctive feature is slightly overexposed and therefore bright white in this image.) Shadows of several thin ringlets within the division can be seen here as well. The dark band that stretches across the centre of the image is the shadow of Saturn’s B ring, the densest of the main rings. Part of the actual Cassini division appears at bottom, along with the A ring and the narrow, outer F ring. The A ring is transparent enough that, from this viewing angle, the atmosphere and threadlike shadows cast by the inner C ring are visible through it. Images taken with red, green and blue filters were combined to create this colour view. The images were obtained with the narrow angle camera on November 7, 2004, from a distance of 3.7 million kilometres (2.3 million miles) from Saturn. The image scale is 22 kilometres (14 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colorado. CREDITS Imaging Sequence Development: Emma Birath, Ben Knowles, Nicole Martin, Josh Riley (CICLOPS/SSI) John Barbara (NASA GISS) Kevin Beurle, Mike Evans (QMUL, England) Doug Dawson, Elizabeth Turtle (Univ of Arizona) Tilmann Denk (Freie Univ, Germany) Kevin Grazier (JPL)Paul Helfenstein, Pauline Helfenstein, Jon Proton, Diane Sherman (Cornell) Thomas Roatsch (DLR, Germany) Ashwin Vasavada (UCLA); Image Release Design/Layout: Carolyn Porco; Image Preparation: Chris Clark, Carolyn Porco; Figure Caption: Preston Dyches Image is courtesy NASA/JPL-Caltech