Evidence for Supersonic Turbulence in the Upper Atmosphere of
Jupiter
Claude Emerich,
*
Lotfi Ben Jaffel,
John T. Clarke,
Renée Prangé,
G. Randall Gladstone,
Joel Sommeria,
Gilda Ballester
Spectra of the hydrogen Lyman 
(Ly-) emission line profiles
of the jovian dayglow, obtained by the Goddard High Resolution
Spectrograph on the Hubble Space Telescope, appear complex and variable
on time scales of a few minutes. Dramatic changes occur in the Ly-
bulge region at low latitudes, where the line profiles exhibit
structures that correspond to supersonic velocities of the order of
several to tens of kilometers per second. This behavior, unexpected in
a planetary atmosphere, is evidence for the particularly stormy jovian
upper atmosphere, not unlike a star's atmosphere.
C. Emerich and R. Prangé, Institut d'Astrophysique
Spatiale, CNRS, F-91405 Orsay, France, and Institut d'Astrophysique de
Paris, CNRS, F-75014 Paris, France.
L. Ben Jaffel, Institut d'Astrophysique de Paris, CNRS, F-75014 Paris,
France.
J. T. Clarke and G. Ballester, Space Physics Research Laboratory,
University of Michigan, Ann Arbor, MI 48109-2143, USA.
G. R. Gladstone, Southwest Research Institute, San Antonio, TX 78238, USA.
J. Sommeria, Ecole Normale Supérieure de Lyon, Lyon, France.
*
To whom correspondence should be addressed.
