JUPITER HE 584 ANGSTROM DAYGLOW - NEW RESULTS

Recent studies of the upper atmosphere of Jupiter and the H Lyman alph a bulge in particular have prompted us to reevaluate Voyager UVS measu rements of Jupiter's He 584 Angstrom dayglow. We employ more sophistic ated data reduction techniques than for earlier analyses to better qua ntify the UVS observations. We model Jupiter's He 584 Angstrom intensi ty using partial frequency redistribution and inhomogeneous atmospheri c models that are more realistic than the isothermal atmospheric model s used in the earlier analyses, These calculations show that the eddy diffusion coefficient at the homopause K-h is roughly 2(-1)(+2): x 10( 6) cm(2) sec(-1), One question we address is whether Jupiter's He 584 Angstrom dayglow shows a longitudinal asymmetry in intensity. The pres ent work suggests that the evidence for such an asymmetry is not concl usive but is consistent with a variation anticorrelated with H Lyman a lpha. (C) 1995 Academic Press, Inc.