NASA | JPL-Caltech | GSFC | Cassini | 2015 Nov 11
[img3="As winter sets in at Titan’s south pole, a cloud system called the south polar vortex (small, bright “button”) has been forming, as seen in this 2013 image.New observations made near the south pole of Titan by NASA’s Cassini spacecraft add to the evidence that winter comes in like a lion on this moon of Saturn.
Credits: NASA/JPL-Caltech/Space Science Institute"]http://saturn.jpl.nasa.gov/images/PIA17177_690.jpg[/img3][hr][/hr]
Scientists have detected a monstrous new cloud of frozen compounds in the moon’s low- to mid-stratosphere – a stable atmospheric region above the troposphere, or active weather layer.
Cassini’s camera had already imaged an impressive cloud hovering over Titan’s south pole at an altitude of about 186 miles (300 kilometers). However, that cloud, first seen in 2012, turned out to be just the tip of the iceberg. A much more massive ice cloud system has now been found lower in the stratosphere, peaking at an altitude of about 124 miles (200 kilometers).
The new cloud was detected by Cassini’s infrared instrument – the Composite Infrared Spectrometer, or CIRS – which obtains profiles of the atmosphere at invisible thermal wavelengths. The cloud has a low density, similar to Earth’s fog but likely flat on top. ...