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The second ring-moon system of Uranus: discovery and dynamics
Mark R Showalter1, Jack J Lissauer
1SETI Institute, 515 North Whisman Road, Mountain View, CA 94043, USA. mshowalter@seti.org
Science (New York, N.Y.)
|December 24, 2005
Summary
Hubble Space Telescope observations of Uranus revealed two new moons and two faint rings. These discoveries orbit outside the main rings, forming a complex and potentially unstable system.
Area of Science:
- Planetary Science
- Astronomy
- Orbital Dynamics
Background:
- Uranus possesses a known system of main rings and classical moons.
- The region beyond the main rings and interior to the large moons was less explored.
Purpose of the Study:
- To investigate the region outside Uranus's main rings using deep exposures.
- To identify and characterize any new moons or ring structures.
Main Methods:
- Utilized deep imaging capabilities of the Hubble Space Telescope.
- Analyzed images to detect faint objects and ring features.
Main Results:
- Discovered two new moons: U XXVI Mab and U XXVII Cupid.
- Identified two new faint rings, one co-orbital with Mab.
- The new features are located outside the main rings but inside the classical moons.
Conclusions:
- The newly discovered moons and rings add complexity to Uranus's outer system.
- This densely packed system exhibits rapid variations and potential instability.
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