[Previous] | [Session 74] | [Next]
J. R. Spencer (Lowell Observatory)
I will review recent observational work on Io from HST and groundbased telescopes. These new observations complement Galileo's close-up data by providing improved resolution and/or coverage in the temporal, spectral, and occasionally even the spatial domains.
Notable recent results have included the detection of chlorine in the Io torus (1); spatially resolved observations of Io's neutral atmosphere from HST (2); UV detection and characterization of Io's plumes from HST (3); very high resolution imaging of volcanic thermal emission from ground-based telescopes using speckle (4) and AO techniques, and from HST (5); ground-based observations of widespread very high temperature volcanism seen also by Galileo (6); and possible correlations between volcanic activity and the brightness of Io's extended sodium nebula (7).
I will also discuss plans, and preliminary results, from the HST campaign of intensive Io observations in support of the Galileo Io flybys (8).
References: (1) Kueppers and Schneider 1999, abstract P32B-12, Spring AGU; (2) Roesler et al. 1999, Science 283, 353; (3) Spencer et al. 1997, GRL 24, 2471; (4) MacIntosh et al. 1998, abstract P22B03, Fall AGU; (5) Goguen et al. 1998, BAAS 30, 1120. (8) McEwen et al. 1998, Science 281, 97; Stansberry et al. 1997, GRL 24 2455; (7) Wilson et al. 1999, this meeting. (8) Bagenal et al. 1999, this meeting.