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B. M. Fisher, G. S. Orton (Jet Propulsion Laboratory/Caltech), J. Lecacheux, P. Drossart (Paris/Meudon Obs.), F. Colas (Bureau des Longitudes), A. Sanchez-Lavega, J. F. Rojas, R. Hueso (UPV, Spain), I. Miyazaki (Japan), D. Parker (USA), A. Garcia (GEA, Spain)
During Jupiter's last solar conjunction, the classical white ovals BC and DE changed into a single white oval, which we here label ``BE''. While the exact details are not known, pre-conjunction tracking showed BC and DE to be approaching each other, suggesting that their interaction resulted in the single remaining spot. We report here preliminary results from recent near- and mid-infrared ground-based data. At 5-\mum, sensitive to deep emission and clouds, the classical white ovals appear as cold regions surrounded by a bright ring. At 3.78-\mum, sensitive to clouds above the 1-bar level, the white ovals appear as oval bright clouds surrounded by a darker ring, quite similar to their visible appearance. Prior to conjunction, the 5-\mum bright rings surrounding BC and DE merged in the region between the ovals, while their oval 3.78-\mum cloud features remained distinct. After conjunction, only one oval remained, nearer the former DE position. The 3.78-\mum morphology shows a distinct oval but without a dark surrounding ring. Contrasting this, 5-\mum observations show no structure. Visible observations show considerable cloud structure but no obvious oval structure. Previous observations of the tropospheric temperature structure has shown white ovals to be cold. Recent ground-based thermal observations have shown BE to follow this legacy, although it appears to be significantly larger than FA (also see Orton {\it et al}. this meeting). From these observations, we conclude that the new BE white oval is either still forming or breaking up. The upper tropospheric clouds and temperatures have structure like FA, but the deeper cloud structure revealed by the 5-\mum observations are not yet formed into a classical white oval organization.