Abundances of ammonia and carbon disulfide in the Jovian stratosphere following the impact of comet Shoemaker-Levy 9

Abstract

Radiative transfer-scattering models were used to fit the Hubble Space Telescope UV spectroscopic observations of Jupiter taken 2.5 hours after the impact of fragment G of comet P/Shoemaker-Levy 9. They yield abundances for NH₃ and CS₂ of (0.25-1.3) × 10¹⁶cm^-2 and (0.43-1.1) × 10¹⁵cm^-2 respectively, at unit optical depth level in the part of the atmosphere above the G-impact site. This range in the abundances is caused by the uncertainty in the composition of the aerosol material and the atmospheric pressure level where the aerosol unit optical depth in the UV occurs. The upper limits of H₂S, PH₃, C₂H₂, and C₆H₆ at the unit optical depth level are 1.2 × 10¹⁶cm^-2, 3.3 × 10¹⁴cm^-2, 1.0 × 10¹⁷cm^-2, and 3.3 × 10¹⁴cm^-2, respectively. The abundance of NH₃ and the upper end of the CS₂ abundance range are now found to be each approximately a factor of two lower than was reported previously [Noll et al., 1995], and H₂S is not detected.