Session 42 - Solar Systems.
Display session, Tuesday, January 16
North Banquet Hall, Convention Center

## [42.14] Near-Infrared Spectroscopy of the Shoemaker-Levy 9 Impact Sites with UKIRT: CO Emission from the L Site and Additional 5 Micron Spectra

T. Y. Brooke, G. S. Orton, D. Crisp, A. J. Friedson (JPL), G. L. Bjoraker (Goddard)

CO emission lines in the 4.7 \mum fundamental vibrational band were detected from Jupiter at the Shoemaker-Levy 9 fragment L impact site on July 20, 1994 UT, up to 4 to 5 hours after impact. For an atmospheric model with a single temperature for the emitting CO, which is assumed to be in local thermodynamic equilibrium (LTE), the CO temperature is estimated to be T(CO)=280\pm10 K. For this case, the CO column density is N(CO)=1.2 \times 10^17 cm^-2 and the estimated mass of CO in the L site is 1.6 \times 10^13 g, with uncertainties of a factor ten. This amount of CO can be plausibly explained as coming from material (O and C) originally in the impactor, though Jovian C could also have contributed. Larger amounts of cool CO below the emitting CO could have been present. The possible departure of the CO vibrational level populations from LTE is discussed qualitatively. There were no discernable long-term changes in the CO line depths of impact sites vs. non-impact sites in the spectra obtained in this work.