47 terms

Earth science review pages (14-23)

Only natural satellite of the Earth
Second brightest object in the sky
Orbits around the Earth about
Has no atmosphere
Maybe water ice in craters and at the poles
The same side of the moon always faces the Earth. Amount of time to rotate once on it's axis= amount of time for the moon to go around the Earth once.
We never see the far side of the Moon (Dark side of the Moon).
Moon facts
interior of the Moon
The moon has a thin crust a thick mantle and a small core
Most of the moon's surface is covered with regolith, which is:
Regolith- mixture of dust and debris produced by meteroid impacts,
Two primary types of terrain on the moon
maria: low areas on the moon that appear dark. Sites of huge impact craters that were later flooded by molten lava
Highlands: Lighter colored areas on the moon which are elevated above the maria
Impact Theory
Earth Collided with a very large object (planet side) and moon was part ejected material. Based on analysis of Moon rocks.
Lunar Phases
The appearance of the moon, as viewed from Earth, at different points along its orbit.
New moon
Moon and sun directly in line
Moon is between the Earth and Sun
Moon can not be seen due to the glare of the sun.
"No moon"
Full Moon
Moon is opposite the sun with the Earth between
"Full" side facing us is illuminated
First quarter moon
Moon is half full and Illuminated on the right and side
Halfway between new moon and full moon.
Third quarter moon
Moon is half full and is Illuminated on the left hand side.
Halfway between full moon and new moon.
Waxing moon
Lighted on the right hand side
After the new Moon and before Full moon
When the lighted portion of the moon's surface is increasing
Waning Moon
Lighted on the left hand side
After the full Moon before the new Moon
When the lighted portion of the Moon's surface is decreasing- Getting darker
Crescent Moon
Phase when less than half the visible part of the Moon is Illuminated
Can have both waxing and waning crescent
Gibbous Moon
Phase when more than half, but less than all, of the moon is illuminated.
Can have both Waxing and Waning Gibbous
Changing appearances of the moons as seen from Earth
Moon phases
Phase of the moon when you see only half of the lighted side after a full moon
Third quarter
Period when the amount of the lighted side that can be seen becomes increasingly smaller
Phase that starts just after the full moon
Waning Gibbous
Period after a new moon when more and more of the lighted side of the moon becomes visible
Phase when the lighted half of the moon is facing the sun and the dark side faces the Earth
New Moon
Waxing of the moon when you can see half of the lighted side, or one quarter, of the moon's surface
1st quarter
Phase of the moon when the half of the moon's surface facing Earth is lighted
Full Moon
Waxing period when more than one-quarter but less than half of the lighted side of the moon's surface can be seen
Waxing Gibbous
Occurs when the moon moves directly between the Sun and the Earth and casts a shadow on part of Earth
Solar Eclipse
Occurs when Earth's shadow falls on the moon
Lunar Eclipse
Dark colored, relatively flat regions of lava on the moon's surface
Occurs just before a new moon
Waning Crescent
The moon rotates on its axis once every 365 days
The moon completes on revolution around Earth every 27.3 days
The large depressions on the moon that are caused by meteorites are called crescents
One half of the moon is always lighted because it faces the sun
At full moon, we see 100 percent of the moon
What is the difference between Waxing and Waning
Waning: The lighted portion of the Moon's surface is decreasing on the left side
Waxing: When the lighted portion of the moon's surface is increasing on the right side.
Lunar Eclipse
Earth's shadow falls over the moon
Safe to watch
0 to 3 each year
Solar Eclipse
occurs when moon passes between Earth and Sun ( moon covers sun).
Only occurs at new moon
Happens at least twice a year
What is the difference between penumbra and Umbra shadows
Penumbra: Faint outer Shadow
partial eclipse are seen from within this shadow
Umbra: Dark inner shadow
Total eclipses are seen from within this shadow
Path of Totality
Track of the moons shadow across the Earth where you will see total solar eclipses. (Long, but narrow area)
Rule of 400
The sun is 400 times bigger than the moon, but the moon is 400 times closer to Earth
So sun and Moon looks like the same size.
Earth tilt
The Earth's axis is tilted 23.5 degrees
Earth Rotation
Rotates at its axis once every 24 hours (1 day) creates day and night. Earth's revolution around sun= 365 days ( 1 year).
Caused by the tilt of the Earth as it orbits the sun
The Earth always leans in the certain times of the year receive more light
Jun 20 or 21st
North Hemisphere is closer to the Sun. Days are long and hotter
First day of summer= longest day of the year
Summer Solstice
December 21 or 22nd
The Northern Hemisphere tilts away from the sun so days are shorter and colder
First day of winter= Shortest day of the year
Winter Solstice
September 22nd or 23rd
First day of Autumn sun is directly over the Equator (Equal of hours and dark).
Days graduating get shorter
Autumnal Equinox
March 20 or 21
First day of Spring the sun's light is directly over the Equator (Equal hours light and dark)
Days gradually getting longer.
Vernal Equinox
Two times a year that the Earth's tilt makes the sun reach its greatest angle north or south making the star of summer and winter
Two times a year that the sun is directly above the Earth's equator and the day and night are equal