The earth's orbit around the earth takes
365 days 1/4
How long does it take for the earth to make one revolution around the sun?
365 days
Spring equinox
March (about the 21st)
Fall equinox
September (about the 21st)
What is unique about the equinox?
The days and nights are nearly equal in length everywhere on earth
Revolution
The earth travels around the sun one full time.
How long does a revolution take?
365 days
Summer solstice
June (about the 21st)
Winter solstice
December (about the 21st)
Describe day and night lengths during the summer solstice
Days are longest in one hemisphere and shortest in the other
What is tilted closest to the sun during the summer (June) solstice?
The North Pole - brings summer to the north hemisphere and winter to the south hemisphere.
True or false: The June solstice is the summer solstice in the northern hemisphere and the winter solstice in the southern hemisphere.
True
What is tilted closest to the sun in the winter (December) solstice?
The South Pole - brings winter to the north hemisphere and summer to the south hemisphere.
True or false: During the winter (December) solstice, the area north of the arctic circle is in constant darkness and the are south of the antarctic circle is in constant daylight.
True
Axis
An imaginary line that runs between the north and south poles. The earth tilts on its axis
Seasons occur due to the
Tilting of the earth on the axis
March equinox
Spring equinox in the northern hemisphere and fall in the southern hemisphere
September equinox
Fall equinox in the northern hemisphere and spring in the southern hemisphere
Rotation
Each turn on the earth's axis. Takes 24 hours
Revolution vs Rotation
Rotation is one complete turn on the axis, takes 24 hours.
Revolution is one complete trip around the sun, takes 365 days.
Time zones
Because the earth rotates toward the east, the days starts earlier in the east than it does in the west. The government created time zones so everyone's days start and stop at the same time. Makes it easier to keep track of the time.
Core
A sphere of very hot metal at the center of the earth.
Inner Core
Solid. Temperatures above 5000 degrees
Outer Core
Hot liquid metal
Mantle
Thick, rocky layer around the core. Temperatures more than 3300 degrees. Able to flow or move. Kind of like a hot stick of butter.
Crust
Thin layer of rocks and minerals that surrounds the mantle. Surface of the crust includes land areas where people live as well as the ocean floor. Movement within the mantle and heat inside the earth help shape the crust.
atmosphere
A thick layer of gases or air above the earth's surface. Keeps oxygen in and heat from the sun out.
Landforms
Shapes and types of Land.
Landforms are shaped by two processes:
Processes BENEATH the surface that push the earth's crust up and processes ON the earth's surface that wear it down.
Water
Covers 75% of the earth's surface or the crust
erosion
Ice, water or wind remove small pieces of rock
Weathering
Breaks rocks down into tiny pieces
Two types of weathering
Chemical and mechanical
Chemical weathering
Rainwater or acids carried by rainwater dissolve rocks
Mechanical weathering
Moving water, ice or sometimes wind breaks rocks into little pieces.
Earth's crust is thinnest
beneath the ocean floor
Earth's crust is the thickest
between high mountain ranges
Weathering and erosion shape the earth's landforms by
breaking down the landforms that are pushed up from forces under the surface.
Sunrise
Sun appears to rise because the earth rotates and turns to face the sun.
Deposition
Process that deposits material eroded (rocks, soil) by water, wind and ice. Can create a sandy beach when rocks and soil are deposited downstream by a river.
Plains
Gently rolling or flat land. Created by material that was carried downstream by rivers a long time ago.
Plate tectonics theory
The earth's crust is made up of huge blocks called plates. (like a puzzle)
Plates
Continents or parts of continents and parts of the ocean floor
magma
Streams of molten, nearly melted rock.
faults
Seams in the earth's crust (places where two plates meet together and rub against each other)
What forces inside the earth shape the earth's surface?
volcanoes and earthquakes
volcanoes
Pressure inside the earth forces magma up through the crust. The cooling lava forms new land forms
earthquakes
Plates slide against each other along fault lines, causing the ground to shake