New Horizons Imaging of Jupiter's Main Ring
Abstract
We have performed an analysis of over 500 images returned by New Horizons' LORRI visible-light camera during the 2007 flyby of Jupiter. We find that: - Radial profiles from New Horizons give unprecedented insight into the ring's structure. The main ring is clearly subdivided into three distinct and complete rings. These rings - between 128,000 km and 129,000 km - have been seen in several earlier individual images from Galileo (Burns et al 2004) but not previously mapped completely. The New Horizons imaging shows them to be continuous and uniform. They are composed predominantly of large grains, and are probably the source of dust in the ring. Inward of 128,000 km, the main ring is predominantly made of small dust grains. - The main ring is less dusty than it used to be. The phase curve indicates that the quantity of large bodies remains similar to that observed by Cassini in 2000 (Throop et al 2004), but the quantity of dust has decreased by a factor of 2-4. - The main ring is azimuthally uniform, with none of the large-scale asymmetry seen in Galileo and earlier observations. We do not identify any clumps beyond than those seen by Showalter et al 2007. - New Horizons clearly detected Jupiter's Amalthea gossamer ring out to roughly 185,000 km. We have not found the fainter Thebe gossamer ring and are unlikely to do so, due to contamination from stray light. This work was supported by NASA's Outer Planets Research program.
- Publication:
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AAS/Division for Planetary Sciences Meeting Abstracts #50
- Pub Date:
- October 2018
- Bibcode:
- 2018DPS....5010409T