Earth and the Moon Flashcards
geologic timelines
precambrian eon
paleozoic era
mesozoic era
cenozoic era
make up 7/8 of earth’s history
precambrian eon
sudden burst of biological diversity as a result of spike in oxygen levels
appearance of invertebrates, bony fishes, amphibious organisms
paleozoic era
age of dinosaurs
mesozoic era
3 periods of mesozoic era
triassic
jurassic
cretaceous
extinction of dinosaurs
theorized to be caused by an asteroid colliding into Earth, covering the atmosphere with soot and toxic gas
largest land mammals have begun to evolve
evolution of Man and primates
cenozoic era
3 kinds of motion of earth
rotation
revolution
precession
spinning of the earth around an imaginary line called axis
rotation
earth’s axis
23.5 degeres
direction of rotation
west to east (view from equator)
counterclockwise (view from northpole)
1 full rotation
one daytime and one nighttime
what does rotation do to the shape of the earth
makes it oblate spheroid
movement of the earth along its orbit
revolution
speed of revolution
around 18 m/s
direction of revolution
counterclockwise
period
365.25 days
day and night are unequal in length
solstice
north pole leans FARTHEST away from the sun
sun strikes directly at the tropic of cancer
winter solstice
north pole leans NEAREST towards the
strikes directly at the tropic of capricorn
summer solstice
day and night are equal in length
equinox
when is vernal equinox
march 20-21
when is autumnal equinox
september 22-23
movement of the Earth revolving alteration in the orientation of its rotational axis
precession
phases of the moon
new moon - waxing crescent - first quarter - waxing gibbous - full moon - waning gibbous - third quarter - waning crescent
illuminated part faces away from the earth
the moon is dark
new moon
half of the illuminated part can be seen
1st quarter
illuminated part can be fully seen
full moon
half of the illuminated part can be seen
third quarter
shape of the moon (illumination) is increasing
waxing
shape of the moon (illumination) is decreasing
waning
crescent
unilluminated part > illuminated part
gibbous
illuminated part > unilluminated part
phenomenons where the earth, moon and sun fall in the same line
eclipse
solar eclipse
sun-moon-earth
lunar eclipse
sun-earth-moon
the celestial body is completely within the umbra
total eclipse
darkest part
umbra
the celestial part is partially in the umbra and extends to penumbra
partial eclipse
lightest part
penumbra
rise and fall of sea levels influenced by the combined gravitational forces exerted by the moon, sun and rotation of earth
tides
gravitational pull of sun and moon combine
results in high high-tides and low low-tides
happens during new moon and full moon
spring tide
sun and moon work at the right angles, causing the bulges to cancel out
results in smaller difference between high and low tides
happens during moon’s quarter phases
neap tide
models of the solar system
geocentric theory and heliocentric theory
geocentric theory
earth is at the center of solar system
heliocentric theory
solar system revolves around the sun
lone natural satellite of earth
rotation and revolution are simultaneous, thus, only one side is visible on earth
lower gravitational force than earth, objects weigh lighter
originated from a large body crashing into the proto-Earth, ejecting molten material which cooled into the moon
the moon
