lundi 15 mai 2017
Short Shadow
NASA - Cassini International logo.
May 15, 2017
The projection of Saturn's shadow on the rings grows shorter as Saturn’s season advances toward northern summer, thanks to the planet's permanent tilt as it orbits the sun. This will continue until Saturn's solstice in May 2017. At that point in time, the shadow will extend only as far as the innermost A ring, leaving the middle and outer A ring completely free of the planet's shadow.
Over the course of the Cassini mission, the shadow of Saturn first lengthened steadily until equinox in August 2009. Since then, the shadow has been shrinking. These changes can be seen by comparing the shadow in the above view to its appearance as Cassini approached Saturn in 2004 (PIA06077), equinox in 2009 (PIA11667), and two years ago, in 2015 (PIA20498).
This view looks toward the sunlit side of the rings from about 10 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Feb. 3, 2017.
The view was acquired at a distance of approximately 760,000 miles (1.2 million kilometers) from Saturn. Image scale is 46 miles (73 kilometers) per pixel.
The Cassini mission is a cooperative project of NASA, ESA (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 mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.
For more information about the Cassini-Huygens mission visit https://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org and ESA's website: http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens
Related links:
PIA11667: https://photojournal.jpl.nasa.gov/catalog/PIA11667
PIA06077: https://photojournal.jpl.nasa.gov/catalog/PIA06077
PIA20498: https://photojournal.jpl.nasa.gov/catalog/PIA20498
Image, Text, Credits: NASA/Tony Greicius/JPL-Caltech/Space Science Institute.
Greetings, Orbiter.ch