PHOSPHINE AND JUPITER'S GREAT RED SPOT

Voyager IRIS (Infrared Interferometer Spectrometer) observations of Jupiter's Great Red Spot (GRS) have been examined in order to extract the vertical distribution of phosphine. To the accuracy than can be achieved from this approach, there appears to be no difference between the PH3 distribution over the GRS compared with the distribution over the neighboring South Tropical Zone. This result is at variance with a pre-Voyager prediction of an enhancement of PH3 over the GRS resulting in the preferential production of red phosphorous in this location on the planet (Prinn & Lewis 1975). The composition of the red material remains an open question.