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We report on spectro-imaging infrared observations of Jupiter's auroral zones, acquired in October 1999 and October 2000 with the FTS/BEAR instrument at the Canada-France-Hawaii Telescope. The use of narrow-band filters at 2.09 and 2.12 [micro]m, combined with high spectral resolution (0.2 [cm.sup.-1]), allowed us to map emission from the [H.sub.2] [S.sub.1] (1) quadrupole line and from several [H.sub.3]+ lines. The [H.sub.2] and [H.sub.3]+ emission appears to be morphologically different, especially in the north, where the latter notably exhibits a 'hot spot' near 150[degrees]-170[degrees] System III longitude. This hot spot coincides in position with the region of increased and variable hydrocarbon, FUV and X-ray emission, but is not seen in the more uniform [H.sub.2] [S.sub.1] (1) emission. We also present the first images of the [H.sub.2] emission in the southern polar region. The spectra include a total of 14 [H.sub.3]+ lines, including two hot lines from the 3[v.sub.2]-[v.sub.2] band, detected on Jupiter for the first time. They can be used to determine [H.sub.3]+ column densities, rotational (Trot) and vibrational ([T.sub.vib]) temperatures. We find the mean [T.sub.vib] of the [v.sub.2] = 3 state to be lower (960 [+ or -] 50 K) than the mean [T.sub.rot] in [v.sub.2] = 2 (1170 [+ or -] 75 K), indicating an underpopulation of the [v.sub.2] = 3 level with respect to local thermodynamical equilibrium. Rotational temperatures and associated column densities are generally higher and lower, respectively, than inferred previously from [v.sub.2] observations. This is a likely consequence of a large positive temperature gradient in the sub-microbar auroral atmosphere. While the signal-to-noise is not sufficient to take full advantage of the 2-D capabilities of the observations, the search for correlations between line intensities, [T.sub.vib] and column densities, indicates that variations in line intensities are mostly due to correlated variations in the [H.sub.3]+ column densities. The thermostatic role played by [H.sub.3]+ at ionospheric levels may provide an explanation. The exception is the northern 'hot spot,' which exhibits a [T.sub.vib] about 250 K higher than other regions. A partial explanation might invoke a homopause elevation in this region, but a fully consistent scenario is not yet available. The different distributions of the [H.sub.2] and [H.sub.3]+ emission are equally difficult to explain. Keywords: Jupiter; Jupiter/atmosphere; Ionospheres infrared observations

The occultation of bright star HIP9369 by the northern polar region of Jupiter was observed from four locations in North and South America, providing four data sets for ingress and egress. The inversion of the eight occultation lightcurves provides temperature profiles at different latitudes ranging from 55[degrees]N to 73.2[degrees]N. We estimate the errors on the profiles due to the uncertainties of the inversion method and compare the value of the temperature at the deepest level probed (~ 50 [micro]bar) with previous observations. The shape of the temperature gradient profile is found similar to previous investigations of planetary atmospheres with propagating and breaking gravity waves. We analyze the small scale structures in both lightcurves and temperature profiles using the continuous wavelet transform. The calculated power spectra of localized fluctuations in the temperature profiles show slopes close to -3 for all eight profiles. We also isolate and reconstruct the three-dimensional geometry of a single wave mode with vertical and horizontal wavelengths of respectively 3 and 70 km. The identified wave is consistent with the gravity wave regime, with a horizontal phase speed nearly parallel to the planetary meridian. Nevertheless, the dissipation of the corresponding wave in Jupiter's stratosphere should preclude its detection at the observed levels and an acoustic wave cannot be ruled out. Keywords: Jupiter; Occultations; Atmospheres, Dynamics; Atmospheres, Structure

Author(s): B. Sicardy (corresponding author) [1, 2]; T. Widemann [1]; E. Lellouch [1]; C. Veillet [3]; J.-C. Cuillandre [3]; F. Colas [4]; F. Roques [1]; W. Beisker [5]; M. Kretlow [...]