ch29 Flashcards
what is a round, three-dimensional object, the surface of which is the same distance from the center in all directions
sphere
what is an elongated, closed curve with two foci
ellipse
is Earth a perfect sphere
no because the diameter is a little bigger than the height of Earth
what are some ancient observations that support the Earth being a sphere
objects fall straight down, shadow of Earth on the moon, in every part of the world we see different stars
what are two things that affect gravitational forces
distance and/or size
which diameter of the earth is longer
the equator
what does the magnetic field do for earth
protects people from solar radiation
which magnetic pole is in the northern hemisphere
south magnetic pole
what magnetic pole is in the southern hemisphere
north magnetic pole
can the poles flip
yes
what degrees is the earths axis tilted
11.7 degrees
what is the flip of the poles called
its called magnetic reversal
how often does the magnetic reversal happen and when did it happen last
200,000 years
780,000 years ago
how often does the magnetic reversal happen and when did it happen last
200,000 years
780,000 years ago
what is a magnetosphere
it deflects harmful radiation from the sun
how are the aurora’s created
is when electrically charged particles colliding with atoms in the atmosphere
what is the scientific name of the northern lights
aurora borealis
what is the name of the southern lights
aurora australis
when is Earth closest to the sun
around early january
140 million kilometers
when is Earth farthest from the sun
around early july
152 million kilometers
what is an area 15 degrees wide in which time is the same
time zone
what is the spinning of earth on its axis
rotation
what is the motion of earth in an elliptical orbit around the sun
revolution
what is defined as a plane of Earth’s orbit around the sun
ecliptic
what occurs when Earth’s rotational axis is tilted directly toward the sun or away from the sun
solstice
at what is earth’s rotational axis perpendicular to a line drawn from the center of earth to the center of the sun
equinox
Who devised a method of timekeeping around 3000 B.C.?
Babylonians
What was the symbol for degree taken from
The Babylonian symbol for the sun
How many degrees does the earth spin in one day
360 degrees
How many hours does it take the earth to make one full rotation
24 hours
How many degrees does the earth spin in one hour
15 degrees
What direction does the sun rise
East
What direction does the sun set
west
T or f- All time zones are the exact same size
False; they are modified to fit around cities, states, and country borders, and other key sites
How many time zones are there in the world
24 time zones
Which direction do you move to add hours to the time
east
Which direction do you move to subtract hours from the time
west
How many time zones are there in the United States
6 time zones
What are the names of the time zones
The Mountain time zone, Eastern time zone
Pacific time zone, Alaskan time zone, Central time zone, and the Hawaiian time zone
What is a solar day
The earth’s rotation from the sun in the sky from noon one day to noon the next day
What is a sidereal day
When a certain star rises above the horizon until that same star rises again
What are the two main reasons for seasons
The axis tilt and how close earth is to the sun
Which 2 seasons have a solstice
Summer and Winter
Which month is the summer solstice
june
Which month is the winter solstice
december
Which two seasons are equinoxes
Spring and Fall
Which month is the spring equinox
march
which month is the fall equinox
september
When is the longest day of the year
During the Summer Solstice
When is the shortest day of the year
During the Winter Solstice
When are the days almost 12 hours of day and 12 hours of night
During the spring equinox and during the fall equinox
what is a rise and fall in the ocean surface
tide
what reflects the change in appearance of the moon as seen from Earth
moon phase
what occurs when the moon moves directly between the sun and the earth and casts shadow on earth
solar eclipse
what occurs when earth passes between the sun and the moon and casts a shadow on the moon
lunar eclipse
what are the dark-colored, flat, lava filled regions on the moons surface
maria
what is a layer of dusty material produced by collisions between asteroids and comets and the moon
regolith
how any days does it take the moon to revolve around the Earth
27.3 days
a complete lunar phase cycle takes 29.5 days, what is this called
synodic month
do we ever see the back side of the moon
no
what causes a tide to rise or fall
the gravitational pulls of the sun and the moon
what is the rise of sea level called
high tide
after the sea rises, how many hours does it take for the sea level drop
about 6 hours
which is farther from Earth, the sun or the moon
the sun
does the moon or the sun cause a greater effect on Earths tides
the moon does
how are the sun, and the moon aligned for a spring tide
they are in straight line
the sun to the earth to the moon
how are the sun, and the moon aligned for a neap tide
a 90 degree angle
what does the phase of the moon you see depend on
the positions of the earth moon and sun relative to each other
when does a new moon occur
it occurs when the moon is between the earth and the sun
how many phases of the moon are there
8 phases of the lunar cycle
what is the definition of waxing phases
us when the illuminated portion of the moon becomes greater and greater every night
what is the definition of waning phases
is when the illuminated portion of the moon gets less and less every night
what are the moon phase names
new moon, waxing crescent, first quarter, waxing gibus, full moon, waning gibus, 3rd quarter, waning crescent
where is the word month derived from
the root word moon
how is the earth,sun,and moon aligned during a solar eclipse
the moon is between the sun and the Earth
how is the earth,sun,and moon aligned during a lunar eclipes
the Earth is between the sun and the moon
how are the depressions on the moon formed
by meteorites, asteroids, and comits
are there mountains on the moon
yes
which side of the moon is thicker
the back side
is the mantle of the moon a solid or liquid
solid
what did the clementine spacecraft do
it confirmed the thickness of the crust and provided information of the rocks on the moon
what did the lunar prospector do
took photographs of the moons surface, collected the evidence of water/ice, confirmed the ironage core
what is the giant impact theory
is a theory the a large sized object collided with earth causing debris to be thrown into orbit that debris condensed into the moon
