Chapter 7 Flashcards
(18 cards)
from above the Earth’s North pole, the direction of travel of the planets around the sun
counterclockwise
terrestial planets
rocky surfaces with craters, mountains/valleys, volcanoes
dense iron cores
high average density
iron, oxygen, silicon, magnesium, nickel, and sulfur
Jovian planets
low average density
interiors made from gas and liquid
Mostly light elements such as hydrogen and helium
Moons of Jupiter
66 known
4 Galilean moons: Io, Europa, Ganymede, Callisto
large satillites
there are 7 large moons “satillites”
the moon, Io, Europa, Ganymede, Callisto, Titan, Triton
Inferior planet period
(1/PinferiorSidereal)=(1/EarthSidereal)+(1/inferiorSynodic)
Spectroscopy of a solid surface
provides broad absorption features instead of lines
ice
solid compounds commonly water (H20), carbon dioxide (C02), methane (CH4), and ammonia (NH3)
atmospheric composition of terrestial and Jovian planets
terrestrial planets have mostly heavy gases because they are hotter and do not have the gravitational force to retain light, hot gases
Jovian planets are cooler and can retain lighter, more abundant gases
asteroids
rocky objects found in the inner solar system
also known as minor planets
orbit the sun in the same direction as the planets
can not contain ice due to heat from the sun
trans-Neptunian objects
found beyond Neptune in the outer solar system and contain both rock and ice
comets
mixtures of rock and ice that originate in the outer solar system but can venture close to the Sun
tail is caused by the vaporization of ice on their surface
may be the result of the collision of two trans-Neptunian objects
kuiper belt
region 30-50 AU from the sun which contains most trans-Neptunian objects
impact craters
created by shock waves from collisions with meteoroids
many have central peaks
active vs inactive planets
active planets have at least a partially molten core
active planets have fewer impact craters due to plate tectonics and other geological activity
Mercury is inactive, Venus is still very active
dynamo
process of producing a magnetic field by the motion of the liquid metal in a planet’s interior
global magnetic field
created by movement of a molten metal core
Mercury is too cool to have a substantial magnetic field
Venus doesn’t rotate fast enough to agitate its molten interior
parts of the surface of a cooled planet remain magnetized
liquid metallic hydrogen
highly compressed Hydrogen which allows electrons to “hop” from one atom to the next
allows massive Jovian planets to have a magnetic field
