Planets Flashcards
(16 cards)
Mercury’s exterior
Uniformly Cratered Slightly larger than moon ~600K in Day, ~100K at Night Slow rotation Ice deposits in permanent shadow
Mercury’s interior
Smaller size means smaller pressure
Made of heavier elements
Large iron core
Why is Mercury’s mag field surprising?
Inside should be cooled and mostly solid, plus rotational period is slow, however still has weak mag field. Large Iron core can release a lot of heat at liquid solid boundary, latent heat of crystallization is released, sending liquid iron core into convective motion
Venus’ exterior
Same size as Earth
Few craters
Surface relatively young (500mil)
Some faults and ridges
Venus’ interior
Average density, similar to Earth
Expected liquid iron core, however no mag field due slow rotation
Why is Venus’ surface so young?
Flake tectonics - Easy for magma to break through and reset due to thin crust
Mars’ exterior
24.5 hour day normal rotation Southern highlands heavily cratered Northern lowlands less cratered and younger Hotspot volcanoes Huge canyons
Mars’ interior
Density similar to earth cooled significantly due to smaller size Northern lowlands could have been resurfaced due to thinner crust residual magnetism in old highland rocks polar caps of frozen CO2
Jupiter’s general properties
320Me, 11Re 165K Average density low - 1300kgm-3 immense pressure in core made of light elements
Jupiter’s structure
Rotational flattening indicate rocky core
outer core made of liquid ice(CH4, NH3, H20) from captured icy meteroids and comets
Bulk of Jupiter made up of liquid metallic H, acts as conductor for mag field
fast rotation helps
Outer layer ordinary H and He
No solid surface
Jupiter’s heat
emits twice the amount of heat energy than it absorbs
Brown dwarf style?
Still cooling from formation
Internal heat due to convection flows
Saturn’s properties
Similar to Jupiter
less massive/less pressure = less dense
Saturn’s ring properties
Thin sheet of orbiting particles
In region where tidal forces would have broken up moons
Uranus’ properties
Smaller the Jupier, similar density
Rocky core surrounded by mantle of compressed water and ammonia
rotational axis perpendicular to orbit
Uranus’ mag field
Pressure high enough for ions to dissolve in liquid
Water and ammonia
Causes a mag field with these as conductors
Aurorae seen
Mag field misaligned and off center
rotation axis off centre
large impact?
Neptune’s properties
More massive than Uranus
Larger rocky core
Internal heat source
