Chapter 29 Flashcards
round, three dimensional object the surface f which is the same distance from the center in all directions
Sphere
an elongated, and comets
Ellipse
Is earth a perfect sphere?
No because the diameter is a little bit longer than the high of Earth
What are some acenched observation that the Earth is round?
Objects fall straight down, shadow of Earth on the moon, in every part of the world we seen different stars
What are two things that affect gravitational forces?
One with bigger mass if they are the same distance apart
the one that is closer will have a greater gravitational pull
What does the magnetic field do for earth?
It protects us from harmful solar radiation
Which magnetic pole is in the northern hemisphere?
South magnetic pole
what degrees is earth axis tilted at ?
11.7 degrees
What is the flipping of the north and south magnetic pole
Magnetic reversals
How often do magnetic changes occur
200,000 years
When was the last one that occurred?
780,000 years ago
What is a magnetosphere?
deflects harmful radiation from the sun
How do auroras get created?
From electrically- charged particles collide with atoms in the atmosphere and emit light
What are the northern and southern lights?
Northern- Borealis
Southern- Australis
When is Earth closes to the sun?
early January which is about 147 million km away
When is the sun farthest away
Early July about 152 million km away
Is an area 15 degrees wide in which the time is the same
Time zone
The spinning of Earth on is´s axis
Rotation
Is the motion of Earth in an elliptical orbit around the sun
Revolution
Is defined as the plane of Earths orbit around the sun
Ecliptic
Occurs when Earths rotational axis is tilted directly toward the Sun or away from the sun
Solstice
Earths rotational axis is perpendicular to a line drawn drawn from the center of Earth to the center of the sun
Equinox
is a rise or fall in the ocean surface
Tide
Reflects the change in appearance of the moon as seen from Earth
moon phase
Occurs when the Moon moves directly between the Sun and Earth and casts a shadow on Earth
solar eclipse
Occurs when Earth passes between the Sun and the Moon and casts a shadow on the Moon
lunar eclipse
These cracks became conduits for lava, which erupted and filled in the craters creating surface features
maria
Is a layer of dusty lunar material produced by collisions between asteroids and comets
regolith
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
True or false. 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?
Mountain time zone Eastern time zone Pacific time zone Alaskan time zone Central time zone 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
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 we ever see the back side of the moon?
No, we do not see the back side we just see one side
What causes a tide to rise or fall?
The gravitational pull of the sun and the moon
After the sea level rises how many hours does it take for the sea level drop?
about 6 hours
Which is father from Earth, the sun or the moon?
Sun
Does the moon or the sun cause a greater effect on Earths tides?
Moon
How are the sun, the earth, and the moon aligned for a spring tide?
The sun, the earth, and the moon are in straight line
How are the sun, the earth, and the moon aligned for a neap tide?
90 degree angles
What does the phase of the moon you see depend on?
Positions of the moon, Earth, and the sun relative to one another
When does the new moon occur?
Occurs when the moon is between the earth and the sun
How many phase of the moon are there?
8 phases of the moon
What is the definition of waxing phases?
the illuminated portion of the moon becomes greater and greater each night
What is the definition of waning phases?
when we see the moon get less and less illuminated
What are the moon phases names?
new Moon. waxing crescent Moon. first quarter Moon. waxing gibbous Moon. full Moon. waning gibbous Moon. last quarter Moon. waning crescent Moon.
Where is the word month derived from?
Comes from the root word moon
How is the earth, moon, and sun aligned during a solar eclipse?
When the moon moves directly between the sun and the Earth
What is an umbra?
The darkest portion of the moon shadow
What is a penumbera?
A partial shadow of the moon that is casted on Earth
How is the earth, moon, and sun aligned during a lunar eclipse?
The earth is between the sun and moon
How are the depressions on the moon formed?
by meteorites, asteroids, and comets
Are there mountains on the moon?
Yes
Which side of the moon is thicker?
The side that doesn’t show
Is the mantle of the moon a solid or a liquid?
Solid
What did the lunar Prospector do?
Took photos of the moons surface, comfired the moon has a small iron rich core, collected evidence that supports the presence of water- ice on the moon
What is the Giant Impact Theory?
A mars size object hit earth that caused debis to hit which continued into large mass known the the moon
