Composition and structure of Jupiter's deep atmosphere

Condensible species ---water, hydrogen sulfide and ammonia--- were all found by the Galileo probe to be greatly depleted to depths well below their equilibrium condensation levels in Jupiter's deep troposphere. Simultaneously, the putative clouds of these species were essentially non-existent. It was revealed that the probe entered a dynamically unique region, a 5-micron hotspot, where local meteorology including desiccated downwelling air depletes the condensible volatiles. A deep, thick (water) cloud elsewhere, suggested by the orbiter imaging of a storm, and the nearly ubiquitous clouds of ammonia support this notion. The ratios (to H) of the heavy elements, S, N, C, Ar, Kr and Xe, were found to be 2-3 × solar, which has important implications for the formation of Jupiter. Preliminary analysis reveals no heavy hydrocarbons in excess of 10 ppb, but the work is continuing.