29 Flashcards
29.1
what are two factors that effect gravitational strength
mass and distance
which diameter of earth is longer
equater
what does the magnetic field protect earth from
harmful radiation from the sun
the south magnetic pole is located in which hemisphere
northern hemisphere
what degree is earths axis tilted at
11.7
do the magnetic poles reverse
yes
what are large scale reversals called
magnetic reversals
how often does the magnetic reversals occur
200,000 years
how long ago was the last magnetic reversal
780,000 years
what part of magnetic field deflects harmful radiation from the sun
magnetosphere
what is the northern and southern lights called
northern- aurora borealis
southern- aurora australis
how are the auroras created
electrically- charged particles collide with atoms in the atmosphere and emit light
elipse
elongated, closed curve with two foci
in which month is earth closest to the sun
January 147 million km away
what month is earth farthest from the sun
July 152 million km away
29.2
time zone
an area 15* wide in which the time is the same
rotation
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 earths orbit around the sun
solstice
occurs when earths rotational axis is tilted directly toward the sun or away
equinox
earths rotational axis is perpendicular to a line drawn from the center earth to the center of the sun
who devised a method of timekeeping around 3000 B.C
babylonians
what was the symbol for degree taken from
was the babylonian symbol for the sun
how many degrees does the earth spin in one day
360
how many hours does it take the earth to make one full rotation
24
how many hours does it take the earth to make one full rotation
how many degrees does the earth spin in one hour
15
what direction does the sun rise
east
what direction does the sun set
west
all time zones are the exact same size t or f
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
which direction do you move to add hours to the time
east
which direction do you move to subtract hours from
west
how many time zones are in the united states
six
what are the names of the time sones
mountain daylight
what is a solar day
full rotation from noon to noon
what is a sidereal day
full night rotation for star to star
what are the two main reasons for seasons
tilt of earth and revolution
which 2 seasons have a solstice
which month is the summer solstice
which month is the winter solstice
which two seasons are equnioxes
which month is the spring equriox
Tide
A rise or fall in the ocean surface
Moon phase
Change in appearance of the moon as viewed from earth, due to the relative positions of earth the sun and the moon
Solar eclipse
Occurs when the moon passes between the sun and earth and casts a shadow on part of earth
Lunar eclipse
Occurs when earths shadow falls on the moon
Maria
Relatively flat dark colored regions on the moon’s surface
Regolith
Layer of loose ground up rock on the lunar surface formed by the accumulation of impact material
How many days does it take the moon to revolve around earth
27.3
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
Gravitational pull of 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
About 6 hours
Which is farther 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
Sun>earth>moon
How are the sun, the earth, and the moon aligned for a neap tide
Sun>earth>90* moon
What does the phase of the moon you see depend on
Depends on the positions of the moon, earth, and sun relative to one another
When does a new moon occur
When the moon is between earth and the sun
How many phases of the moon are there
8
What is the definition of waxing phases
What is the definition of waning phases
What are the moon phase names
- new
- waxing crescent
- 1st quarter
- waxing gibbous
- full
- waning gibbous
- 3rd quarter
- waning crescent
Where is the word month derived from
How is the earth, moon, and sun aligned during a solar eclipse
What is an umbra
Where the total eclipse happens
What is a penumbra
Partial solar eclipse
How is the earth, moon, and sun aligned during a lunar eclipse
How are the depressions on the moon formed
Are there mountains on the moon
Which side of the moon is thicker
Is the mantle of the moon a solid or a liquid
What did the Clementine spacecraft do
It confirmed the thickness of the crust on the moon and it provided information on the material content of moon rocks
What sis the Lunar Prospector do
Took pictures of moons surface, confirmed the moon has a small iron rich core, evidence that there is water on the moon
What is the Giant Impact Theory
They think a
Mars sized object collided on earth where debris was thrown into orbit which condensed into a large mass forming the moon
