TEXES Spectral Mapping of Jupiter and Saturn and the Origins of Giant Planet Nitrogen

We report spectral mapping of the atmospheres of Jupiter and Saturn in February 2013 using the Texas Echelon cross Echelle Spectrograph (TEXES, [1]) mounted on NASA’s Infrared Telescope Facility (IRTF). The purpose of these observations was (i) to study jovian meteorology via measurements of temperature, wind shear, humidity (i.e., ammonia content) and cloud coverage; (ii) to assess the aftermath of Saturn’s northern 2010-2011 storm, including the continued existence of the stratospheric anticyclonic vortex [2]; and (iii) to determine precise estimates of the 15 N/ 14 N ratio on both planets to constrain the origins of nitrogen to the gas giants. Mid-infrared observations of this nature complement spacecraft observations from Cassini, Juno and, ultimately, JUICE.