Earth/Moon System Flashcards
North end of the axis points towards______
Polaris, the Northstar
Definition of rotation
The spinning of a planet on its axis
The sun and moon seem to move because of earth’s _______
Rotation
A point of the equator rotates about__________
1,600 km per hour
What does rotation cause
Day and night
It is _____ on the side of the earth that is facing the sun
Day
It is _____ on the side of the earth facing away from the sun
Night
Definition of revolution
Movement of one object around another object (ex:planets around the sun)
1 complete revolution around the sun is called a ______
Year
What is our orbit not?
A circle
If earths axis were straight up and down, day relative to the sun temperatures would _______ _________ year-round
Remain constant
If temperatures remained constant, there would be no _______
Seasons
Why does earth have seasons?
It’s axis is tilted
Our axis is tilted at an angle of ___ from the vertical
23.5 degrees
When the north end of earths axis is towards the sun, the northern hemisphere has ______
Summer
When the southern end of earths axis is tilted toward the sun, the northern hemisphere has _____
Winter
Summer and winter are not affected by _______
Changes in earths distance from the sun
Definition of axis
Imaginary line that passes through earths center and the north and south pole
(June 21) which end of earths axis is tilted toward the sun
The north end
June 21
Noon sun is directly overhead at ______ latitude- in the tropic of _____
23.5 degrees north, cancer
Define latitude
Measurement north and south of the equator
June 21
The northern hemisphere will receive more or less hours of sunlight
More
Southern Hemisphere will receive more or less hours of daylight and less direct rays therefore it will have the coolest temps of the year and will be in _____
Winter
Dec. 21
Which end of earths axis is tilted toward the sun?
Southern
Dec.21
Noon sun is overhead at what degrees and over which tropic?
23.5 degrees latitude and the Tropic of Capricorn
Dec. 21 the Southern Hemisphere having _____
Summer
When the sun is over head at either 23.5 north or 23.5 south latitude they are called_____
Summer and winter solstices
What occurs halfway between the solstices when neither hemisphere is tilted toward the sun?
Equinoxes
What does Equinox mean?
Equal light
On the equinoxes the length of day and night are ______
Equal
Vernal equinox is the ______ Equinox that occurs on _____ 21st and is the beginning of _____ in the _____ hemisphere
Spring equinox
March
Spring
Northern
Autumnal equinox- occurs around ________ and is the beginning of ___ in the _____ hemisphere
September 23rd
Fall
Northern
On the dates of the equinox the sun is directly over the ______
Equator
How many days does the moon take to revolve around the earth? And how long does it take for the moon to complete one rotation?
27.3 days
Moons orbit is a what?
Eclipse
Why are the moons days and years equal?
Because the moons revolution around earth and its rotation both take 27.3 days to complete
Why can we see the moon?
Because it reflects the Suns light
What are phases?
different shapes of the moon
The moon goes through all of its phases in one ____
Revolution
Solar eclipses can only occur during which moon phase?
New moon
Define umbra
Darkest part of the moon’s shadow
People within the umbra experience what kind of eclipse?
A total eclipse
Define corona
The shiny halo like disk around the darkened sun during a solar eclipse
Define penumbra
Larger part of the moon’s shadow that is not as dark
How does the sun look from the penumbra during a solar eclipse?
The sun is partially visible
Lunar eclipses only occur during which moon phase?
Full moon
A total lunar eclipse happens when:
The moon is in earths umbra
