CH 29 Flashcards
How many degrees does the earth spin in an hour?
360 degrees
What was the symbol for degree taken from?
Taken form the sun
Who devised a method of timekeeping around 3000 B.C.?
Babylonians
When is the earth furthest away from the sun
July
When is the earth closest to the sun
January
How are auroras created?
Electrically charged particles collide with atoms in the atmosphere and emit light
Scientific name of southern and northern lights
Northern- Aurora Borealis
Southern- Aurora Australis
Within Earth’s magnetic field,deflects
Magnetospshere
When was the last magnetic reversal?
700,080 years ago
how often do magnetic reversals happen
Every 200,000 years
what is it called when magnetic poles switch
Magnetic reversal
Can magnetic poles flip flip
Yes
At what degrees is earth’s axis tilted
11.7 degrees
Which magnetic pole is located in the South Pole
North magnetic pole
Which magnetic pole is located in the north pole
In the south magnetic pole
What does the magnetic field protect the Earth from?
Harmful radiation
What are two factors that effect gravitational pull
Mass and distance
sphere
a round, three-dimensional object, the surface of which is the same distance from the center in all directions
ellipse
an elongated , closed curve with two foci
time zone
an area 15 degrees wide in which the time is the same
rotation
is the spinning of Earth on its axis
revolution
the motion of Earth in an elliptical orbit around the sun
ecliptic
defined as the plane of Earth’s orbit around the Sun
solstice
occurs when Earth’s rotational axis is tilted directly toward the sun or away from the sun
equinox
Earth’s rotational axis is perpendicular to a line drawn from the center Earth to center of the sun
What direction does the sun rise?
east
How many hours does it take earth to make one full rotation?
24 hours
What direction does the sun set?
west
True or false. All time zones are the same exact 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
What are the names of the time zones?
Atlantic/Alaskan, Pacific, Mountain, Central, Eastern, and Hawaiian
How many time zones are there in the United States?
6 time zones
What is solar day?
Sun one day at noon to sun at noon the next day
What is a sidereal day?
one certain star one night the next day gets replaced
Which 2 seasons have a solstice?
winter and summer
What are the two main reasons for seasons?
tilt of the axis and revelution
Which month is the summer solstice?
june 21st
Which month is the winter solstice?
december 21st
Which two seasons are equinoxes?
spring and fall
Which month is the spring equinox?
march 21st march 22nd
Which monthly is the fall equinox?
September 22nd or 23rd
When is the longest day of the year?
June 21st
When is the shortest day of the year?
december 21st
When are the days almost 12 hours of day and 12 hours of night?
march 21st and 22nd and september 22nd or 23rd
tide
a rise or fall in the ocean surface
moon phase
reflects the change in appearance of the moon as seen from Earth
solar eclipse
occurs when the Moon moves directly between the Sun and Earth and casts a shadow on Earth
lunar eclipse
occurs when Earth passes between the Sun and Moon and casts a shadow on the moon
maria
are the dark-colored, flat, lava-filled regions on the Moon’s surface
regolith
a layer of dusty lunar material produced by collisions between asteroids and comets and the Moon
how many days does it take the moon to revolve around Earth?
27.3 days
a complete lunar phase cycle takes 29.5 days, what is this called ?
synodic month
do you ever see the backside of the moon?
no
what causes a tide to rise or fall?
the gravitational pulls the sun and moon
what is the rise of sea level called?
high tide
after the sea level rises how many hours does it take for the sea level drop?
six hours
which is farther from Earth, the sun or the moon?
sun
does the moon or the sun cause a greater effect on Earth’s tides?
the moon
how are the sun, the earth, and the moon aligned for a spring tide?
the sun the earth and the moon are in a straight line
how are the sun, the earth, and the moon aligned for a neap tide?
sun earth moon make a 90 degree angle
what does the phase of the moon you see depend on?
position of the moon, earth, and the sun relative to one another
when does a new moon occur?
when the moon is between the earth and the sun
how many phases of the moon are there?
8
what is the definition of waxing phases?
illuminated portion that we see appears larger each night
what is the definition of waning phases?
the illuminated portion we see see begins to look smaller
what are the moon phase names?
new moon, waxing crescent, 1st quarter, waxing gibbous, full, waning gibbous, 3rd quarter, and waning crescent
where is the word month derived from?
moon
how is the earth, moon, and sun aligned during a solar eclipse?
sun moon and earth
what is an umbra?
the fully shaded inner region of a shadow cast by an opaque object
what is a penumbra?
partial eclipse
how is the earth, moon, and sun aligned for the lunar eclipse?
sun, earth, and moon
how are the depressions on the moon formed?
craters
are there mountains on the moon?
yes
which side of the moon is thicker?
far side
is the mantle of the moon a solid or a liquid?
solid
what did the Clementine spacecraft do?
confirmed that the crust of the side facing earth is thinner than the other side
what did the Lunar Prospector do?
took surface photos of the moon, confirmed has iron rich coal, evidence that supports the presence of water- ice on the moon
what is the Giant Impact Theory
mars-sized object collided with Earth, sending debris into orbit, remainder condensed into a large mass, forming the moon
