Midterm Flashcards
What’s the difference between planets and dwarf planets?
Dwarf planets have not cleared the area around their orbit, and they aren’t satellites
What sphere takes up the most space on earth?
Hydrosphere
How old is the earth?
4.5 billion years old
What type of lava has the lowest silica content?
Komatiite
What type of rock has the highest viscosity?
Rhyolite
What are fluvial systems?
water controlled structures
What are eolian deposits?
Wind controlled structures
What is mass wasting?
Gravity controlled structures
What layer makes up the most of the earth’s mass?
mantle
What are p-waves?
push-pull waves, slow down going through fluids
What are s-waves?
shear waves, don’t go through fluids at all
What is the structure of the earth core?
Outer is liquid, inner is solid
What are the main elements in the earth?
Iron and oxygen
When did the highest rate of heat flow occur?
Hadean eon
Where does the most heat loss occur?
At plate boundaries
How are primary and secondary craters different?
Primary: circular, secondary: elliptical
What’s the smallest type of crater?
Simple
What’s the largest type of crater?
Multi-ring basins
What’s the order of events in crater formation?
Compression, excavation, modification
What happens in the compression step?
fracturing, brecciation, melting, and vapourization
What happens in the excavation step?
there is explosive expansion and large amounts of debris
What happens in the modification step?
slumping of crater walls
What is degradation?
Later impacts in an existing crater
What is a meteorite?
Remains of meteoroids on earth
What is a meteoroid?
Small, solid particles in space
What is a meteor?
visible path of a meteoroid as it enters earth’s atmosphere
What layer do meteoroids fragment in?
stratosphere
Where do meteorites come from?
asteroid belt
What are most meteorites made of?
stony material
What type of meteorites have chondrules?
stony
What is the light called that’s emitted from a meteoroid as it explodes in the atmosphere?
bolide
What is a fireball?
A meteor brighter than Venus
What is the most common gas in the atmosphere?
Nitrogen, then oxygen
What is the atmospheric structure?
troposphere, stratosphere, mesosphere, thermosphere, exosphere
Which sphere absorbs UV?
stratosphere
What is white light?
made up of all colours
What has the shortest wavelength?
Gamma rays
As wavelength increases, frequency….
decreases
How does wind travel relative to isobars on a non rotating planet?
perpendicular
What is the Coriolis effect?
freely moving objects are deflected (northern hemisphere to right, southern hemisphere to left)
What type of centres do cyclones have?
Low pressure
Where does the solar wind first encounter the magnetosphere?
bow shock
What is a Van Allen belt?
charge particles are stored in upper electron and lower proton belts
What causes aurora borealis?
when charged particles excite gas molecules to higher energy levels which emits light
When was there high heat flow and earth’s internal structure formed?
Hadean era
When was the continental nuclei formed and origin of life?
Archean eon
What was the atmosphere made up of in the archean eon?
carbon dioxide and water from volcanoes
What happened in the biosphere in the archean eon?
prokaryotes, asexual reproduction
When was the stabilization of continental platforms and oxidation of atmosphere, along with well developed oceans?
Proterozoic eon
What was the biosphere like in the proterozoic eon?
from asexual to sexual reproduction, explosion of life near end of eon
When was the modern plate tectonic period and expansion of life?
Phanerozoic eon
When did organisms get skeletons?
phanerozoic eon
What is the mean solar day?
24 hours, time from one noon to the next
how long is a sidereal day?
23 hours, blah blah
What is revolution?
motion of a celestial body around some point in space
Perihelion
closest to sun (winter)
Aphelion
furthest from sun (summer)
What is precession?
very slow shifting of the direction of the earth’s axis
What is the celestial equator?
projection of the earth’s equator onto celestial sphere
What is the equinox?
equal day and equal night
What is the winter solstice”?
shortest day, longest night
Summer solstice?
longest day, shortest night
what is waxing?
increasingly illuminated west side of moon
what is waning?
decreasingly illuminated east side of moon
how long does it take to see all the phases of the moon?
4 weeks
what is synchronous orbit?
revolution == rotation
when does a total lunar eclipse happen?
when the moon is fully within the earth’s umbra
when does an annular eclipse occur?
eclipse happens at the apogee
partial lunar eclipse?
moon is in part of the earth’s umbra
what is a spring tide?
higher than normal, sun and moon aligned
what is a neap tide?
lower than normal high tides, sun and moon not aligned
