WATER BROUGHT INTO JUPITER ATMOSPHERE BY FRAGMENT-R AND FRAGMENT-W OFCOMET-SL-9

Measurements of H2O in the impact plumes of the a and W fragments of C omet SL-9 were made from the Kuiper Airborne Observatory, Water emissi ons peaked similar to 12 min after the impacts, and indicate a tempera ture similar to 1000 K based upon the relative radiances of two H2O em ission features at 6.62 and 6.45 mu m. Our analysis shows that the wat er was probably delivered by Comet SL-9 and is not of jovian origin, a nd that the C/O ratio in the plume was less than unity. Our calculatio ns, which allow for entrainment of jovian air and use a Halley-like co mposition far the impactor, show that the R fragment contained ice equ ivalent to a sphere 90 m in diameter, On the further assumption that w e only saw 10% of the material, the diameter of the fragment would be 250 m. (C) 1996 Academic Press, Inc.