GEOL 3045: Planetary Geology Lysa Chizmadia Uranus’ Moons Lysa Chizmadia Uranus’ Moons

Introduction  27 named moons –Named after Shakesperian & Alexander Pope characters  Groups –Shepherding Moons –Chaotic Moon Swarm –Puck, Mab & Cupid –Large Inner Satellites –Outer Irregular Satellites  27 named moons –Named after Shakesperian & Alexander Pope characters  Groups –Shepherding Moons –Chaotic Moon Swarm –Puck, Mab & Cupid –Large Inner Satellites –Outer Irregular Satellites Image from:

Shepherding Moons  Keep outer epsilon ring well defined  Cordelia –Inner shepherd –15km in diameter  Ophelia –Outer shepherd –16 km in diameter  Must be inner shepherds, but not yet discovered  Keep outer epsilon ring well defined  Cordelia –Inner shepherd –15km in diameter  Ophelia –Outer shepherd –16 km in diameter  Must be inner shepherds, but not yet discovered Image from:

Choatic Moon Swarm  Orbital parameters highly chaotic –Probably collide with each other regularly  8 small satellites –Bianca (21 km radius) –Cressida (33km radius) –Desdemona (27 km radius) –Juliet (42km radius) –Portia (54km radius) –Rosalind (27km radius) –Belinda (33km radius) –Perdita  Orbital parameters highly chaotic –Probably collide with each other regularly  8 small satellites –Bianca (21 km radius) –Cressida (33km radius) –Desdemona (27 km radius) –Juliet (42km radius) –Portia (54km radius) –Rosalind (27km radius) –Belinda (33km radius) –Perdita Images from:

Puck, Mab & Cupid  Puck –77km radius –Orbital period: 0.76 days –Inclination: 0.31 degrees  Mab –16 km radius –Orbital period: 0.92 days  Cupid –12km radius –Orbital period: 0.61 days  Puck –77km radius –Orbital period: 0.76 days –Inclination: 0.31 degrees  Mab –16 km radius –Orbital period: 0.92 days  Cupid –12km radius –Orbital period: 0.61 days Image from:

Major Satellites  Miranda –Smallest of 5 –Huge fault canyons  Ariel –Brightest & very young surface –Intersecting valleys  Umbriel –Darkest & ancient –Mysterious bright ring  Titania –Largest moon  Oberon –Heavily cratered  Miranda –Smallest of 5 –Huge fault canyons  Ariel –Brightest & very young surface –Intersecting valleys  Umbriel –Darkest & ancient –Mysterious bright ring  Titania –Largest moon  Oberon –Heavily cratered Image from: Image from:

Miranda  Diameter: 470 km  Orbital period: 1.4 days  Eccentricity:  Inclination: 4.23  (high)  Density: 1.20 g/cm 3  Fault canyons –20km deep  Mixture of young & old terrains –Jumbled together –Tidal forces?  Diameter: 470 km  Orbital period: 1.4 days  Eccentricity:  Inclination: 4.23  (high)  Density: 1.20 g/cm 3  Fault canyons –20km deep  Mixture of young & old terrains –Jumbled together –Tidal forces? Image from:

Ariel  Diameter: 1156 km  Orbital period: 2.5 days  Eccentricity:  Inclination: 0.26   Density: 1.67 g/cm 3  Mixture of heavily cratered terrains & smooth plains  Dry ice detected on surface  Interconnected valleys –Chasmata –100s km long –>10 km deep –Floors smoothed by fluid  Diameter: 1156 km  Orbital period: 2.5 days  Eccentricity:  Inclination: 0.26   Density: 1.67 g/cm 3  Mixture of heavily cratered terrains & smooth plains  Dry ice detected on surface  Interconnected valleys –Chasmata –100s km long –>10 km deep –Floors smoothed by fluid Image from:

Umbriel  Diameter: 1169 km (~ Ariel)  Orbital period: 4.14 days  Eccentricity:  Inclination: 0.36   Density: 1.40 g/cm 3 (~ Ariel)  Very old, heavily cratered surface  Mysterious bright ring –Wunda –140 km diameter  Diameter: 1169 km (~ Ariel)  Orbital period: 4.14 days  Eccentricity:  Inclination: 0.36   Density: 1.40 g/cm 3 (~ Ariel)  Very old, heavily cratered surface  Mysterious bright ring –Wunda –140 km diameter Image from: Wunda

Titania  Orbital period: 8.7 days  Eccentricity:  Inclination: 0.34   Density: 1.72 g/cm 3  Largest moon of Uranus  Mixture of cratered terrains & interconnected valleys –Largest trench 1600km long –Faults  internal forces  Orbital period: 8.7 days  Eccentricity:  Inclination: 0.34   Density: 1.72 g/cm 3  Largest moon of Uranus  Mixture of cratered terrains & interconnected valleys –Largest trench 1600km long –Faults  internal forces Image from: Image from:

Oberon  Diameter: 1523 km  Orbital period: 13.5 days  Eccentricity:  Inclination: 0.10   Density: 1.64 g/cm 3  2nd Largest moon of Uranus  Heavily cratered w/ bright rays  S hemisphere has large faults  Diameter: 1523 km  Orbital period: 13.5 days  Eccentricity:  Inclination: 0.10   Density: 1.64 g/cm 3  2nd Largest moon of Uranus  Heavily cratered w/ bright rays  S hemisphere has large faults Image from: 6 km high

Outer Irregular Satellites  Retrograde & highly inclined  5 moons –Caliban –Stephano –Sycorax –Prospero –Setebos  Retrograde & highly inclined  5 moons –Caliban –Stephano –Sycorax –Prospero –Setebos Image from: Image from:

Summary  Inner shepherd moons –Cordelia & Ophelia  Puck, Mab & Cupid  Largest –Miranda: heavily cratered terrain mixed w/ smooth blocks –Ariel: brightest & has chasmata with smooth floors –Umbriel: darkest & has bright ring crater on N pole –Titania: largest moon & mixture of cratered terrain & trenchs & faults –Oberon: highly cratered  Outer irregular satellites –Retrograde & highly inclined –Probable captured asteroids  Inner shepherd moons –Cordelia & Ophelia  Puck, Mab & Cupid  Largest –Miranda: heavily cratered terrain mixed w/ smooth blocks –Ariel: brightest & has chasmata with smooth floors –Umbriel: darkest & has bright ring crater on N pole –Titania: largest moon & mixture of cratered terrain & trenchs & faults –Oberon: highly cratered  Outer irregular satellites –Retrograde & highly inclined –Probable captured asteroids