Saturn’s Skyline

A look along Saturn's sunlit limb

A raw image from Cassini taken on January 9, 2011, this minimally-composed image is actually quite fascinating (IMO): it’s a look at the upper levels of Saturn’s atmosphere in methane wavelength! Yes, Saturn is a gas giant and most of its volume is made up of hydrogen and helium, but there are layers of its atmosphere that are composed of other compounds such as methane, ammonia and phosphine. These high-level hazes rise above the stormy cloudtops and are visible as darker bands along the limb of the giant planet.

At the time of this writing Cassini will be preparing to perform its closest flyby of Saturn’s moon Rhea. passing over its surface at an altitude of a mere 43 miles. Using its dust analyzer and plasma and radio wave instruments to study the rate of dust ejected from meteorite impacts on Rhea, Cassini will attempt to give researchers some insight to the composition and age of Saturn’s rings. (And get some great photos at the same time!) Stay tuned for select images from the flyby to be posted here tomorrow!

Image: NASA / JPL / Space Science Institute