Dr. G. Randall Gladstone will reduce and analyze existing observations that were taken with the Fourier Transform Spectrometer (FTS) instrument at the Canada-France-Hawaii Telescope (CFHT) in 1999 and 2000 of Jupiter's H3+ and H2 auroral emissions at infrared (IR) wavelengths near 2 micron. With the FTS in spectroimaging (BEAR) mode, 14 high-resolution interferogram cubes were obtained that contain bright H3+ and H2 emission lines from the northern and southern auroral regions. Careful analyses of these data will provide information on the spatial distribution of composition, temperature, and ion and neutral wind velocities in Jupiter's thermosphere. Preliminary reduction indicates electrojet-type winds of up to 6 km/s (apparently supersonic, since the expected thermal speed is 2-3 km/s). Preliminary derived temperatures are about 35% lower in the northern aurora than in the south, while derived H3+ column densities in the south are about an order of magnitude lower than in the north.
Further reduction of these data can provide an unprecedented window on the dynamics and energetics of Jupiter's upper atmosphere and will yield much needed constraints for a newly-developed Jupiter Thermosphere General Circulation Model {JTGCM). Our understanding of the upper atmosphere of Jupiter has changed very rapidly over the last decade, primarily as a result of a great wealth of data from ground-based observatories {e.g., CFHT, IRTF), Earth-orbiting observatories {e.g., HST, Chandra), and spacecraft {e.g., Voyager, Ulysses, Galileo, Cassini). A model such as JTGCM is required to help make sense of all these data, but finding suitable model constraints is quite difficult. The CFHT data to be reduced and analyzed here provide the only information on the spatial distribution of Jupiter's high-altitude ion and neutral winds available for the foreseeable future. These observations were made as part of an international collaboration involving several colleagues from the Observatoire de Paris-Meudon and the Institut d' Astrophysique de Paris. ***
