Jupiter's Gossamer Rings Explained

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Jupiter's Gossamer RingsExplained!
Doug Hamilton U. Maryland
Review
What causes the Thebe Extension? Is
there a Thebe Gap?
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Components of the Jovian Ring
Amalthea Ring
Galileo Data Burns et al. 1999
Main Ring
Gap?
Thebe Extension
Thebe Ring
Halo
Keck Data de Pater et al. 1999
Amalthea Ring
Gap?
Thebe Ring
Halo
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Galileo DDS Data
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Shadow Resonanceon a Charged Dust Grain
To Sun
Shadow
Horanyi and Burns 1991
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Shadow Resonance
Coupled oscillations in a, e, and angle between
Sun and pericenter
Eccentricity is much larger than expected!
Semimajor Axis increases significantly.
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Edge-on View of the Thebe Ring
particle size3.2 microns
1.1o inclination of the Thebe Ring
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Gaileo Lines of Sight
Asymmetric Jovian RingsNumerical Model

• Galileo's Lines of Sight

size3.2 microns
Thebe Extension
Thebe Gap
To Sun
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Shadow Resonance Summary

• 1 Dominates dynamics of micron-sized grains in
  both the Thebe and Amalthea Rings.
• 2. Explains the Thebe Extension and the Thebe
  Gap.
• 3. Large eccentricities, so Thebe is a sink of
  ring grains.
• 4. Causes the Gossamer Rings to be
  Self-Sustaining.
• 5. Ejects a broad range of grain sizes outward.