Friday, November 20, 2009

Scene Seen in the Near-Infrared

Friday, November 20, 2009

Cassini's camera looks in near-infrared light at a dramatic view of Saturn, its ringplane and the shadows of a couple of its moons.

The large shadow south of the equator is that of the moon Tethys (1062 kilometers, 660 miles across). The small shadow near the limb of the planet, north of the equator, is the shadow of the moon Mimas (396 kilometers, 246 miles across).

Saturn's northern and southern latitudes appear dark in this image because of the camera filter used. This view uses a spectral filter sensitive to absorption of certain wavelengths of light by methane in Saturn's atmosphere. Compared to the equatorial region which appears bright, in the dark northern and southern latitudes the light at these wavelengths reaches slightly greater depth before being reflected off the cloud tops and it passes through more light-absorbing methane along the way.

This view looks toward the northern, sunlit side of the rings from just above the ringplane.

The image was taken with the Cassini spacecraft wide-angle camera on Oct. 23, 2009 using a spectral filter sensitive to wavelengths of near-infrared light centered at 890 nanometers. The view was acquired at a distance of approximately 2.6 million kilometers (1.6 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 110 degrees. Image scale is 149 kilometers (92 miles) per pixel.

The Cassini Equinox Mission is a joint United States and European endeavor. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini Equinox Mission visit


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