Evidence for methane escape and strong seasonal and dynamical perturbations of Neptune's atmospheric temperatures

  title={Evidence for methane escape and strong seasonal and dynamical perturbations of Neptune's atmospheric temperatures},
  author={Glenn S. Orton and Thérèse Encrenaz and C{\'e}dric Leyrat and R. C. Puetter and A. James Friedson},
  journal={Astronomy and Astrophysics},
Aims. We studied the distribution of mid-infrared thermal emission from Neptune to determine the spatial variability of temperatures and the distribution of trace constituents, allowing us to determine the relative strengths of radiation and dynamics in its atmosphere. Methods. Mid-infrared images of the planet were taken at the Very Large Telescope on 1–2 September 2006. Results. These images reveal strong inhomogeneities in thermal emission. 17.6 and 18.7-µm images exhibit strong seasonally… 

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