A Unified Atmospheric Model for Uranus and Neptune

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https://eos.org/research-spotlights/a-unified-atmospheric-model-for-uranus-and-neptune

By Morgan Rehnberg, Eos/AGU. 

Excerpt: In a new model, three substantial atmospheric layers appear consistent between the ice giants. The ice giants, Uranus and Neptune, are the least understood planets in the solar system. They remain the only worlds that an orbital spacecraft has not visited. Our limited understanding of them derives largely from the flyby of NASA’s Voyager 2 probe and subsequent observations with the Hubble Space Telescope. Yet the ice giants may be most representative of the extrasolar planets in our local vicinity. Why these planets appear so different in color despite having very similar physical properties, including vertical temperature profile and atmospheric composition, is a mystery. Past investigations have attributed Neptune’s deeper blue largely to excess absorption in the red and near infrared from atmospheric methane. ...Irwin et al. attempt to fill this gap by developing a single atmospheric model consistent with the spectral observations of both planets. They fit near-infrared spectra collected by Hubble, as well as the ground-based Gemini and NASA Infrared Telescope Facility(IRTF) telescopes, to a three-layer aerosol model.…

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