Vasavada, A., Porco, C., Ingersoll, A., West, R., and Del Genio, A. (2001). "Jovian Meteorology as Revealed Cassini Time-Lapse, Multispectral Imaging." European Geophysical Society XXVI General Assembly PS6.01.


Abstract

The Cassini encounter with Jupiter combines the best features of the Voyager and Galileo encounters. Like Voyager, Cassini spends three months at low phase angles taking pictures of the day side at regular intervals of 10 or 20 hours. Like Galileo, Cassini has a CCD camera that is sensitive in the near infrared where strong and weak methane bands give information on vertical structure of the clouds. Cassini's ultraviolet sensitivity, which Galileo lacks, gives further information about clouds and hazes at high altitudes. Cassini's best spatial resolution is not as good as Galileo's (60 km vs. 25 km, respectively), but Cassini will return many more images from the planet. Cassini will yield the first three-dimensional global movies of the clouds over an extended period of time. Post-flyby images of the night side will reveal details of lightning and auroras. One goal is to measure winds and document the complex interactions of jovian vortices -- merging, orbiting, creation, filamentation, and interaction with the zonal jets. Another goal is to document the occurrence of moist convection - those areas with lightning discharges, rapid expansion, and cloud growth to high altitude -- and understand its role in the maintenance of the large scale structures like the zonal jets and long lived ovals. A third goal is to re-measure the horizontal eddy momentum flux, to see if it is into or out of the jets. This talk will feature the latest imaging products, including high-resolution movies, and some preliminary discussion of how they relate to the scientific goals.