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Abstract :
[en] The Cassini Ultraviolet Imaging Spectrograph (UVIS) observed Jupiter in a 4-sec integration "high time-resolution mode" on Jan 8, 13-14, and 20-21 in 2001. In this mode Extreme-Ultraviolet and Far-Ultraviolet spectra were obtained with reduced spectral and spatial resolution in order to study rapid variations in H2 band and H Lyman alpha emission. Previous work has shown that the region inside Jupiter's main auroral ovals contains highly variable spots of emission (auroral flares) that persist for typically 1 or 2 minutes. This duration is similar to that in Jupiter's quasi-periodic (QP) radio bursts. We compare UVIS data to simultaneous Galileo Plasma Wave Subsystem (PWS) and Cassini Radio and Plasma Wave Subsystem (RPWS) observations. Jan 8 was an active period for UV variability, that we associate with polar auroral flares. There is a correlation between the radio and UV bursts in this period, suggesting that they are related phenomena. We will also explore coordinated Hubble Space Telescope Imaging Spectrograph (STIS) time-tagged UV images from Dec 14 and Dec 16, 2000, and Jan 13-14, and Jan 20-21, 2001 to study the spatial properties of the auroral flares. The auroral emissions inside the main oval were most prominent in the Dec 14, 2000 HST data. We acknowledge support from the Cassini Project, the Space Telescope Science Institute, and the NASA OSS Minority University Initiative.