Nos tutelles

CNRS

Nom tutelle 1

Nos partenaires

Nom tutelle 2 Nom tutelle 3

Rechercher





Accueil > Séminaires > Archive des séminaires d’Utinam > Archive des séminaires d’astrophysique (jusqu’en 2011) > 2009

Storms, Seasons and Surprises in Gas Giant Atmospheres

par Edith Burgey -

Lundi 15 juin 2009

Glenn S. Orton

Jet Propulsion Laboratory - California Institute of Technology

Résumé :

A plethora of new information is being revealed on the atmospheres of the gas giants of our solar system : Jupiter, Saturn, Uranus and Neptune, using infrared sensing. This talk will highlight the changing characteristics detected from the infrared, primarily from thermal emission, for : temperatures, distribution of condensible and disequilibrium molecules and cloud / haze layers in the atmospheres of the four giant planets. These have been obtained from the Galileo Jupiter orbiter PPR experiment, the Cassini CIRS experiment at Saturn, the Hubble WFPC2 and ACS imaging experiments, together with high-SNR IRS spectra of Uranus and Neptune. These results have been augmented by ground-based observations from NASA’s Infrared Telescope Facility which have provided long-term surveillance of Jupiter and Saturn, coupled with recent observations of all four planets with unprecedented spatial resolution in the mid infrared from the Very Large Telescope, Subaru Telescope and Gemini Telescopes. With this unprecedented detail, new time-dependent phenomena have been discovered. Among them are : a smaller cousin of Jupiter’s Great Red Spot which underwent a dramatic color change and cooldown, long-term vertical waves and ephemeral horizontal waves in Saturn, cooling of the entire north polar region of Uranus, and a wandering stratospheric polar hot spot in Neptune. Current missions such as Herschel and future missions, such as JUNO and the proposed Europa-Jupiter System Mission will continue these detailed and long-term studies in new spectral regions and in greater detail. Continued work from ground-based platforms such as those above, plus newer facilities which could include extremely large telescopes, will continue to open a new era of understanding detailed dynamical phenomena in these atmospheres.