GEOL 3045: Planetary GeologyGEOL 3045: Planetary Geology

Lysa ChizmadiaUranus’ Moons

Lysa ChizmadiaUranus’ Moons

IntroductionIntroduction 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: http://solarsystem.nasa.gov/planets/profile.cfm?Display=Moons&Object=Uranus

Shepherding MoonsShepherding 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: http://solarsystem.nasa.gov/planets/profile.cfm?Object=Ura_Cordelia

Choatic Moon SwarmChoatic 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: http://solarsystem.nasa.gov/planets/profile.cfm?Display=Moons&Object=Uranus

Puck, Mab & CupidPuck, 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: http://www.solarviews.com/eng/puck.htm

Major SatellitesMajor 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: http://en.wikipedia.org/wiki/Moons_of_Uranus

Image from: http://www.daviddarling.info/images/Uranus_moons.jpg

MirandaMiranda Diameter: 470 km Orbital period: 1.4 days Eccentricity: 0.0013 Inclination: 4.23 (high) Density: 1.20 g/cm3 Fault canyons

– 20km deep Mixture of young & old

terrains– Jumbled together– Tidal forces?

Diameter: 470 km Orbital period: 1.4 days Eccentricity: 0.0013 Inclination: 4.23 (high) Density: 1.20 g/cm3 Fault canyons

– 20km deep Mixture of young & old

terrains– Jumbled together– Tidal forces?

Image from: http://www.daviddarling.info/encyclopedia/U/Uranusmoons.html

ArielAriel Diameter: 1156 km Orbital period: 2.5 days Eccentricity: 0.0012 Inclination: 0.26 Density: 1.67 g/cm3 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: 0.0012 Inclination: 0.26 Density: 1.67 g/cm3 Mixture of heavily cratered

terrains & smooth plains Dry ice detected on

surface Interconnected valleys

– Chasmata– 100s km long– >10 km deep– Floors smoothed by fluidImage from: http://www.daviddarling.info/encyclopedia/U/Uranusmoons.html

UmbrielUmbriel Diameter: 1169 km (~ Ariel) Orbital period: 4.14 days Eccentricity: 0.0039 Inclination: 0.36 Density: 1.40 g/cm3 (~ Ariel) Very old, heavily cratered

surface Mysterious bright ring

– Wunda– 140 km diameter

Diameter: 1169 km (~ Ariel) Orbital period: 4.14 days Eccentricity: 0.0039 Inclination: 0.36 Density: 1.40 g/cm3 (~ Ariel) Very old, heavily cratered

surface Mysterious bright ring

– Wunda– 140 km diameter

Image from: http://www.daviddarling.info/encyclopedia/U/Uranusmoons.html

Wunda

TitaniaTitania Orbital period: 8.7 days Eccentricity: 0.0011 Inclination: 0.34 Density: 1.72 g/cm3 Largest moon of Uranus Mixture of cratered

terrains & interconnected valleys– Largest trench 1600km long– Faults internal forces

Orbital period: 8.7 days Eccentricity: 0.0011 Inclination: 0.34 Density: 1.72 g/cm3 Largest moon of Uranus Mixture of cratered

terrains & interconnected valleys– Largest trench 1600km long– Faults internal forces

Image from: http://www.daviddarling.info/encyclopedia/U/Uranusmoons.html

Image from:http://www.solarviews.com/eng/titania.htm

OberonOberon Diameter: 1523 km Orbital period: 13.5 days Eccentricity: 0.0008 Inclination: 0.10 Density: 1.64 g/cm3 2nd Largest moon of

Uranus Heavily cratered w/ bright

rays S hemisphere has large

faults

Diameter: 1523 km Orbital period: 13.5 days Eccentricity: 0.0008 Inclination: 0.10 Density: 1.64 g/cm3 2nd Largest moon of

Uranus Heavily cratered w/ bright

rays S hemisphere has large

faultsImage from: http://www.daviddarling.info/encyclopedia/U/Uranusmoons.html

6 km high

Outer Irregular SatellitesOuter Irregular Satellites Retrograde & highly

inclined 5 moons

– Caliban– Stephano– Sycorax– Prospero– Setebos

Retrograde & highly inclined

5 moons– Caliban– Stephano– Sycorax– Prospero– Setebos

Image from: http://en.wikipedia.org/wiki/Moons_of_Uranus

Image from: http://www.solarviews.com/eng/caliban.htm

SummarySummary 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