Rings, moon

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Saturn's rings are the most spectacular

A ring, B ring, C ring, Cassini Division

all the Jovian planets have rings!

Uranus' and Neptune's rings have been discovered from the ground

Ring structure is due to orbital resonance with moons - the orbital period of particles and the period of moons are close to the ratios of small integers, 1:2 or 2:3 (reason for gaps within rings)

Roche limit:

as a large body gets too close to a much more massive body, the difference in gravity on the opposite sides of it becomes strong enough to break it apart

Galilean satellites: Io, Europa, Ganymede, Callisto

regular satellites orbit by equator

irregular satellites - retrograde (opposite rotation) motion with larger inclinations

Io is the most volcanic object in the solar system

Hyperion looks like a tumbling sponge

Mimas has a freaky crater

Iapetus looks like it has a moldy side

Pan looks like a tortellini

Titan - orbits Saturn, has atmosphere, methane exists as liquid (could support life using H2)

Miranda, Titania, Ariel, Umbriel, Oberon orbit Uranus

Neptune's satellites, Nereid is eccentric but near equator, Triton is retrograde with a thin N2 atmosphere, likely a captured moon

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Pluto:

orbital period: 248 years

Semimajor axis: 39 AU

rotation: 6.4 days

5 known moons: Charon, Nix, Styx, Hydra, Kerberos