Class Notes: Jupiter, Saturn, Uranus, Neptune, and Moons (PDF)

CLASS NOTES: -the terrestrial planets all formed inside the frost line Interior of Jupiter: - heavy stuff sinks to the core; rest is gases and ice. - pressure = how much force a gas is pushing against a surface → jupiter's atmosphere at the top; pressure is not squished very much. pr...

CLASS NOTES: -the terrestrial planets all formed inside the frost line Interior of Jupiter: - heavy stuff sinks to the core; rest is gases and ice. - pressure = how much force a gas is pushing against a surface → jupiter's atmosphere at the top; pressure is not squished very much. pressure gets stronger and stronger as you get in → thousands of gases squishing → density gets so high that it becomes metallic hydrogen ; liquid and solid hydrogen. -hydrogen is a gas but under enough pressure it can become a solid → rocky core, metallic hydrogen, molecular hydrogen, upper atmosphere; old model. JUNO SPACE PROBE - orbits jupiter now; jupiter's structure effects juno's orbit → were able to determine mass distrubition of jupiter. JUPITER IS: DILLUTE CORE AND ENRICHED ENVELOPE? How? - medium size planet smashed into jupiter and mashed up its core → jupiter gets all stirred up and hasn't resettled yet. CORE GOT BROKEN UP AND SPREAD THROUGHOUT THE WHOLE PLANET. JUPITER'S STORMS -complex clouds and stable storms; winds are super fast. -bands (unsure) and storms stable over decades are super thick; 3000km. orange bands? white bands? - distrubited in depth white bands are water clouds. - different gases become liquids at diff temps. lower pressure, higher temperature -? ammonium hydrosulfide clouds → orange bands chemical layers SATURN - second largest → not heavy, not condensed. mass is less than jupiter. hexagon storm at saturn's north pole - centre is a huge hurricane URANUS - ice giant - coldest planet, small rocky core (maybe) - thick water + ammonia + methane mantle - thick h2/he atmosphere - rotation axis tilted 98 degrees → huge collision - think rings and lots of moons. NEPTUNE -furthest jovian planet from the sun; very similar to uranus -rotation axis tilted 28 degree; some collision -more surface features than uranus -strongest winds in the solar system MOONS: IO - tons of volcanoes; no craters EUROPA - ice structure; no craters GANYMEDE - ice structure; some but no craters CALLISTO - tons of creaters MOST GEOLOGICALLY ACTIVE → LEAST GEOLOGICALLY ACTIVE --- IO - small things cool quickly - cant be geologically active! \^most geologically active object in the solar system! EUROPA - surface covered with uncratered ice; new surface; may be a huge ocean beneath the surface. core → ocean → ice GANYMEDE - little larger than Earth's moon got craters, looks like europa but not geologically active. CALLISTO - surface is very heavily cratered SATURN'S LARGEST MOON - TITAN -surface features hidden by thick clouds; lot like venus -has an atmosphere IAPETUES - white and reflective - black dirt sprinkled all over this moon - very old cratered surface - mostly made of ices - white is the natural color - brown is a thin layer over the ice - giant ridge along the equator on the dark side. RHEA: A Moon of Saturn -heavily cratered ball of ice; iapetus without the dirt. ENCELADUS: A moon of Saturn - has had geological activity; super reflective - some parts are cratered and some are not -active methane geysers HYPERION - a moon of saturn -heavily cratered; dark material in the bottom of the craters, very porous - 40% empty space. URNAUS MOON: Miranda: -some craters -high ice content -strange geological features NEPTUNE: TRITON - super cold - surface is mainly frozen nitrogen - almost no atmosphere - geologically active - orbits neptune backwards CLASS 19: RINGS AND VOLCANOES - TIDES IN THE JOVIAN SYSTEMS terrestrial planets: hot core → hot magma, convection cells brings heat up to the surface and causes geological activity; volcanoes. geological activity - coming from the core - heat small planet, cools quicker → no convection → more geologically dead. \^not the case with jovian moons! - tides -IO: A MOON OF JUPITER - continous mess of eruptions - around the same size as the earth's moon. -crazy place - Io\'s small size suggests it should have cooled quickly and become geologically inactive. EUROPA: MOON OF JUPITER - uncratered ice - smoothest object in the solar system. -suggest that europa is covered by a huge salty ocean under the ice - not sure if life exists or if there even is an ocean -tidal forces on Io are greater than in the Earth-moon system because jupiter is large - IO is tidally locked. - In an elliptical orbit, tidal forces would be greater when IO is close to jupiter than when it is far from Jupiter. -squeezing and unsqueezing -this changes force heats up the moon. - but heating up Io takes energy out of the orbit, so it gradually becomes circular? -IO goes around 4 times, Europa goes around twice, Ganymede goes around once. - pulls the orbit into being slightly elliptical. IO is the most geologically active bc it has an elliptical orbit close to Jupiter therefore it has extreme tidal heating. -europa is moderate LEAST ACTIVE: further from Jupiter, less tidal heating MYSTERY \#2 - SATURN'S RINGS: -super complex if **the moons starts a little slower**, what will happen to its path? - it will be in an elliptical orbit, with the perigee a little closer to Jupiter SATURN'S RINGS: possibility \#1: A moon ventured too close to Saturn and was torn apart by tidal forces, stretching and breaking until it became a ring possibility \#2: rings formed at the time of the formation of the solar system, gas couldn't form moons it just stayed as a disk. - outer particles in a ring orbit slower than particles in an inner ring; all bands in a ring travel at diff speeds. - tidal forces from known moons can create gaps furthermore, moons in the rings deflect particles that pass too close to it. - pan moon has a frill -some of the gaps are caused by orbital resonances and some of the gaps are caused by small moons orbiting in the disk sheppard moons - a lot of the structure in the rings is caused by gravitational interactions with small moons orbiting outside the rings or inside the rings. -composition of the material in the rings varies as you go across the rings