Computer Science
Scientific paper
Jul 2003
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003hst..prop.9988f&link_type=abstract
HST Proposal ID #9988
Computer Science
Hst Proposal Id #9988
Scientific paper
The icy Galilean satellites form an integral but poorly understood component of Jupiter's magnetospheric system. While the Pioneer and Voyager spacecraft encounters yielded evidence for the existence of a source of oxygen ions beyond Io's orbit, conclusive evidence that Europa and Ganymede possess thin oxygen atmospheres was only recently provided by HST/GHRS detections of faint far-UV airglow emissions of OI. Moreover, the OI emission on Ganymede is localized to the region of the satellite's poles, consistent with an auroral excitation source that would be expected from the internal magnetic field of Ganymede. More recently, spectrally resolved images of Ganymede obtained with STIS have confirmed this result and demonstrated the variation in location and brightness of the OI emissions with the position of Ganymede relative to Jupiter's plasmasheet. The energy and source of the exciting electrons remain unknown and there is little or no relevant in situ Galileo data that bear directly on this question and thus the determination of the molecular abundance remains highly uncertain. However, the energy can be constrained by the observation of the forbidden OI red line at 6300 Ang, but this requires observation when the satellite is in Jupiter's shadow, to avoid the emissions being swamped by the strong solar reflected light. Europa similarly shows the UV OI emissions, and recent HST/STIS observations show a complex time-dependent variation in the spatial distribution of these emissions. Europa does not have an intrinsic magnetic field, but rather the Jovian field at Europa is modified by a magnetic field induced by Europa's rotation. We will investigate Kivelson's suggested European conducting ocean by timing observations to coincide with different orientations of the induced magnetic field.
No associations
LandOfFree
Jovian Satellites does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Jovian Satellites, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Jovian Satellites will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1133854