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CASSINI MISSION

Saturn, light on the north pole

From Cassini's archive, new pictures and data. The mission ended on Sept. 15 2017

Reflected sunlight is the source of the illumination for visible wavelength images such as the one above.  However, at longer infrared wavelengths, direct thermal emission from objects dominates over reflected sunlight.  This enabled instruments that can detect infrared radiation to observe the pole even in the dark days of winter when Cassini first arrived at Saturn and Saturn's northern hemisphere was shrouded in shadow. 

Now, 13 years later, the north pole basks in full sunlight. Close to the northern summer solstice, sunlight illuminates the previously dark region, permitting Cassini scientists to study this area with the spacecraft’s full suite of imagers. 

This view looks toward the northern hemisphere from about 34 degrees above Saturn’s ringplane. The image was taken with the Cassini spacecraft wide-angle camera on April 25, 2017 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 752 nanometers.  

The view was acquired at a distance of approximately 441,000 kilometers from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 111 degrees. Image scale is 26 kilometer per pixel.  

The Cassini spacecraft ended its mission on Sept. 15, 2017

The Cassini mission is a cooperative project of NASAESA and the Italian Space Agency.  

ASI is one of the partners of the Cassini mission: on the basis of a cooperation agreement with NASA it has developed for Cassini the high gain antenna with the incorporation of a low-gain antenna (that ensure telecommunications with the Earth for the entire duration of the mission), the VIMS spectrometer, the radio-science subsystem (RSIS) and the radar which also uses the high-gain antenna.   

ASI has also developed for the Huygens spacecraft the ASI instrument which measured the physical properties of the atmosphere and Titan's surface.