Presentation #100.07 in the session “Giant Planets 1: Jupiter”.
The identity of the coloring agent(s) in Jupiter’s atmosphere and the exact structure of Jupiter’s uppermost cloud deck are yet to be conclusively understood. The Crème Brûlée model of Jupiter’s tropospheric clouds presumes that the chromophore measured by Carlson, R. W., et al. 2016, Icarus, 274, 106 (the “Carlson chromophore”) is the singular coloring agent in Jupiter’s troposphere in a thin layer above a thick tropospheric cloud deck. In this work, we test the validity of the Crème Brûlée model of Jupiter’s atmosphere using spectra measured during the Juno spacecraft’s 5th perijove pass in March 2017. These data were obtained as part of an international ground-based observing campaign in support of the Juno mission using the NMSU Acousto-optic Imaging Camera (NAIC) at the 3.5-m telescope at Apache Point Observatory in Sunspot, NM. We find that the Crème Brûlée model cloud layering scheme can reproduce Jupiter’s visible spectrum both with the Carlson chromophore and after modifying its complex index of refraction spectrum. While the Crème Brûlée model provides reasonable results for quiescent regions of Jupiter’s cloud bands such as the North Equatorial Belt and Equatorial Zone, we find that it is not a safe assumption for unique weather events, such as the 2016-2017 Southern Equatorial Belt outbreak that was captured by our measurements. We also find that in regions of vigorous upwelling and overturning of fresh material, such as the Equatorial Zone and the South Equatorial Belt outbreak, we can retrieve a “younger” version of the Carlson chromophore that appears to be much less exposed to UV radiation. This work was supported by NASA’s Minority University Research and Education Project (MUREP) NASA Fellowship Activity through training grant number 80NSSC18K1701 and by Research Support Agreement 1569980 from the Jet Propulsion Laboratory, as a subaward of a NASA/Solar System Observations grant.