as101 lesson 11

Mars

Terrestrial planet

Mars orbit

4th planet; average 1.52 AU; year

Mars orbit shape

Eccentric orbit (0.093) causes stronger southern summers

Mars geology

Largest volcano Olympus Mons; giant canyon Valles Marineris; old lava plains; many craters

Mars water evidence

Past rivers/lakes likely; present water mostly ice/permafrost; polar caps contain CO2 ice + water ice

Mars atmosphere

Very thin (~0.007 bar); mostly CO2, some N2 and Ar

Mars magnetic field

No strong global field today; weak crustal remnants suggest past dynamo

Mars moons

Phobos + Deimos; small irregular likely captured asteroids

Phobos fact

Orbits faster than Mars rotates, rises west sets east, spiraling inward

Mars exploration

Viking landers, Pathfinder/Sojourner, Spirit, Opportunity, Phoenix, Curiosity

Jovian planets

Jupiter, Saturn, Uranus, Neptune

Jovian classification

Outer planets; gas/ice giants; low density; large size; many moons; ring systems

Jovian composition

Mostly H + He (especially Jupiter/Saturn); Uranus/Neptune richer in ices like water, ammonia, methane

Jovian orbit trend

Farther from Sun → longer years (Jupiter 11.9 y to Neptune 164.8 y)

Jovian rotation

Fast rotation causes short days + polar flattening

Jovian seasons

Jupiter little due to small tilt; Saturn/Neptune seasons; Uranus extreme seasons from 98° tilt

Jovian moons

Many natural satellites; Jupiter has Galilean moons, others also have large moon systems

Jovian magnetic fields

All strong magnetospheres; Jupiter strongest by far

Why Jupiter has strong field

Rapid rotation + metallic hydrogen interior generates dynamo

Jupiter atmosphere visible features

Alternating belts + zones caused by convection/circulation + cloud chemistry

Zones on Jupiter

Rising cooler air; ammonia clouds; lighter/white bands

Belts on Jupiter

Descending warmer air; fewer ammonia clouds; darker reddish/tan bands

Jupiter winds

Very fast jet streams, strongest near equator

Great Red Spot

Long-lived giant high-pressure storm larger than Earth

Jupiter interior

Cloud tops → gas H/He → liquid hydrogen → metallic hydrogen → dense rocky/icy core (~10 Earth masses)

Saturn interior

Like Jupiter but less metallic hydrogen, more liquid hydrogen, lower density

Uranus + Neptune interior

No metallic hydrogen layer; rocky core with icy mantle + gaseous outer layers

Planet size fact

Jupiter largest planet; more massive than all other planets combined except Sun dominates syst