DPS 34th Meeting, October 2002
Session 18. Outer Planet Atmospheres
Poster, Chair(s): , Tuesday, October 8, 2002, 3:30-6:00pm, Exhibit Hall

[Previous] | [Session 18] | [Next]

[18.14] Mesospheric CH4 and ionospheric H3+ emission in the CASSINI/VIMS observations of Jupiter at mid-latitudes

P. Drossart (Obs. Paris), K.H. Baines (JPL), G. Bellucci (IFSI, Rome), J.P. Bibring (IAS, Orsay), R.H. Brown (U. Arizona), B.J. Buratti (JPL), F. Capaccioni, P. Cerroni (IASF, Rome), R.N. Clark (USGS, Denver), A. Coradini (IASF, Rome), D.P. Cruikshank (NASA/Ames), V. Formisano (IFSI, Rome), R. Jaumann (DLR, Berlin), Y. Langevin (IAS, Orsay), D. Matson (JPL), T.B. McCord (U. Washington), V. Mennella (U. Naples), R.M. Nelson (JPL), P.D. Nicholson (Cornell U.), B. Sicardy (Obs. Paris), C. Sotin (U. Nantes), VIMS Team

Cassini/VIMS observations during the Jupiter encounter between December 2000 and January 2001 give the first opportunity to study phase angle variations of H3+ emission at 3.5~\mum, together with fluorescence CH4 emission at a high level of sensitivity. Spectral images with long integration time (640 ms) are used, for maximum sensitivity. The spectrum of Jupiter in the 3.3-3.6~\mum range exhibits H3+ thermal emission and CH4 emission, interpreted as due to fluorescence of solar light (Drossart et al., ESA-SP427 1999). Synthetic spectra confirms this later detection, first seen on ISO/SWS at a global scale on the disk, and reproduces the P/Q/R branches of the \nu3 band of CH4.\\ Limb profiles of the CH4 emission are obtained for various phase angles, between 0 and 70 dg, which give a new constraint on the mesospheric sounding.\\ On the other hand, limb profiles of H3+ thermal emission are consistent with a H3+ density controlled by the solar flux, confirming the solar control on the H3+ density in equatorial and mid latitude regions, in contrast with high latitude auroral emissions.

If the author provided an email address or URL for general inquiries, it is as follows:

[Previous] | [Session 18] | [Next]

Bulletin of the American Astronomical Society, 34, #3< br> © 2002. The American Astronomical Soceity.