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Spectroscopic observations of Jupiter at thermal–infrared wavelengths were performed on November 8–9 and December 14, 1994, 16 and 21 weeks after the fragments of comet Shoemaker–Levy 9 collided with Jupiter. Residual stratospheric ammonia was searched for in emission at 930.76 cm−1over the longitudes corresponding to the remnants of the D/G/R/S impact sites. We believe a small amount of ammonia may have been detected in November, but report an upper limit for both dates. The constant volume mixing ratio for pressure levels less than 10 mbar that best fits the observation on November 8 is no more than 3.6 ± 2.4 × 10−10. This upper limit decreased to ≤2.3 ± 3.0 × 10−10on December 14. These values are equivalent to upper limits of 1.9 ± 1.2 × 10−10on November 8 and ≤1.2 ± 1.5 × 10−10on December 14 if we adopt a constant volume mixing ratio above a base at 100 mbar. We also searched, without success, for stratospheric ammonia on November 9 over the K/W and L impact site remnants. Our upper limits place stronger constraints on the stratospheric ammonia lifetimes and photochemical depletion models.

The Solar Occultation in the InfraRed (SOIR) instrument onboard Venus Express sounded the Venus mesosphere and lower thermosphere using solar occultation geometry between April 2006 and December 2014. The observations were all taken at the terminator. This paper reports on the water vapor vertical distribution above the clouds and geo-temporal variations, observed across the whole Venus Express mission. Water vapor profiles are sampled between 80 and 125 km from both the morning and evening side of the terminator. Calculations of the water vapor volume mixing ratio agree with those from previous studies, having an average atmospheric profile that varies between 0.56 ppmv and 2.45 ppmv. No significant variations were observed in observations taken between the morning and evening terminator. Short term variations of several Earth days dominate the data set, varying by up to a factor 18 over a 24 h period, from ~10 ppmv to ~0.55 ppmv at an altitude of ~111 km. Similar to previous trace gas observations by SOIR (HCl, HF and SO2), no significant spatial or long term trends are observed.