Planetary Science Seminar spring-2015

Saturn has an axial tilt of 26.7deg and therefore experiences seasons during it’s 29.5 year orbital period around the Sun. CIRS (Composite Infrared Spectrometer) observations from the Cassini spacecraft acquired from 2004 (upon arrival to Saturn) to present cover approximately a Saturnian season and have allowed the effects of seasonal change on Saturn’s temperature and composition to be tracked. In addition, CIRS data acquired in 2009/2010 captures Saturn approximately one Saturnian year after the Voyager flybys in 1980/1981 during which IRIS (Infrared Interferometer Spectrometer) observations were acquired. A comparison of atmospheric properties from IRIS and CIRS therefore allows internannual variability to be explored. An retrieval analysis of Cassini-CIRS and Voyager-IRIS observations has been conducted in order to investigate the seasonal and interannual variability of Saturn’s stratosphere.