1. Solar System
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2. SOLAR SYSTEM The Solar System consists of: Sun
Click here for definition
The Solar System consists of:
Sun
objects that move around it
Planets
their moons
Asteroids (small rocky bodies)
Our Sun is a star at the center of our solar system.
Every object in the system follows their own independent
path, or ORBIT around the Sun.
GREAT VIDEO: Explore the Solar System!
SOLAR SYSTEM
definition
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3. Moon
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4. Some planets have more than one moon Some planets have none
The Moon
Some planets have more than one moon
Some planets have none
A moon is a satellite
A body that orbits a larger body
Artificial satellites also circle earth
The moon takes approx. 29 ½ days to circle earth
Roughly 1 month
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5. Our Sun
Our sun is small compared to some other stars
100 times the diameter of our planet
93 million miles from earth

6. Earth
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7. Geographers study Earth’s rotation, revolution to understand why:
tropics are warm
arctic regions are cold
day is warmer than night
& the tilt of its
axis
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8. Rotation

9. One complete spin of Earth on its axis is called rotation.
Each rotation takes 24 hours, or one day.
Earth turns on its axis, (but to us it appears that the Sun is moving)
definition
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10. …about one second every 10 years.
FACT
The Earth’s rotation is slowing down very slightly over time…
…about one second every 10 years.
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11. Revolution

12. One complete orbit around the sun.
REVOLUTION
One complete orbit around the sun.
It takes the Earth one year, or one revolution, to orbit the Sun
More precisely, it takes 365 ¼ days
LEAP YEAR
Every fourth year becomes leap year
An extra day- February 29th – is added
Allows for this fraction of a day
Keeps the calendar accurate
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13. ANSWER… How fast is the earth revolving around the sun? QUESTION…
revolves around the Sun at a speed of about 18.5 miles/sec
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14. Axis

15. Earth’s axis is tilted, or slanted, at an angle of 23.5˚
An imaginary line that runs from the North Pole through Earth’s center to the South Pole.
Earth’s axis is tilted, or slanted, at an angle of 23.5˚
Because of Earth’s tilt, as Earth revolves around the Sun…
the angle at which the Sun’s rays strike
the planet is constantly changing
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16. ANSWER… How fast is the earth spinning around its axis? QUESTION…
At the equator, the Earth's surface moves 40,000 kilometers in 24 hrs
A speed of about 1040 miles/hr
toward either pole, this speed decreases to almost zero
(since the circumference of the spinning
circle at the extreme latitudes approaches zero)
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17. Day It takes the Earth 23.93 hours to rotate around its axis once
Year It takes the Earth days to orbit the Sun once.
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18. Summary Earth spins on its axis:
an invisible line through the center of the Earth.
North Pole:
The northernmost point of this axis
South Pole:
The southernmost point of this axis
Equator:
invisible line that encircles the widest point of the Earth
The Equator is the same distance away from each pole at every point along it.
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19. Seasons

20. POLAR REGIONS: TROPICS Areas in the low latitudes near the equator
Sun’s rays are nearly vertical throughout the year.
POLAR REGIONS:
Areas near the North and South Poles
The Sun’s rays are always at a low angle.
Result; Poles are generally the coldest places on earth
(click below for “illustrated” definitions)
The Arctic Circle: Circles the North Pole
Antarctic Circle: Circles the South Pole
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21. SEASONS A year is divided into periods of time called seasons:
Each season is known for certain type of weather based on…
temperature
amount of precipitation
Seasons Change as Earth orbits the Sun
The amount of solar energy received , changes
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22. Next

23. Solstice

24. The Earth orbits, on average, 93 million miles from the Sun.
June 21st
December 21st
Solstices:
The 2 days when the Sun’s vertical rays are farthest from the equator
Solstices occur twice a year:
June 21
December 21
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25. Summer solstice Winter solstice Next NORTHERN HEMISPHERE
the Sun's rays strike Earth directly at the Tropic of Cancer
June 21st
longest day of the year
beginning of summer
Winter solstice
shortest day of the year
December 21st,
North Pole is pointed away from the Sun
the Sun’s rays strike Earth directly at the Tropic of Capricorn
SOUTHERN HEMISPHERE
the seasons are reversed
winter solstice is June 21
summer solstice is December 21
MIDDLE LATITUDE REGIONS
lie between:
the Tropic of Cancer & the Arctic Circle
the tropic of Capricorn & the Antarctic Circle.
CLICK for “illustrated” definitions
CLICK for “illustrated” definitions
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26. From mid-Autumn into mid-Winter,
SOLSTICES AND THE SUN...
From mid-Autumn into mid-Winter,
the South pole is tilted toward the sun;
this is when the Northern hemisphere experiences shorter hours of daylight.
The South pole now experiences the 24-hour daylight, right around the time of the Winter solstice.
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27. From mid-Spring through mid-Summer,
SOLSTICES AND THE SUN...
From mid-Spring through mid-Summer,
the North pole is tilted toward the sun;
this is when the Northern hemisphere experiences longer hours of daylight.
The North Pole has several days of total sunlight right around the solstice
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28. Earth's axis tilt & equatorial plane compared with its plane of orbit
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CLICK HERE for an Excellent Video on Equinoxes and Solstices etc.

29. Equinox

30. definition
Equinoxes
The two days of the year when the Sun’s rays strike the equator directly.

31. NORTHERN HEMISPHERE SOUTHERN HEMISPHERE Spring Equinox
the Sun's rays strike Earth directly
Every place on earth has 12 hrs of day & 12 hrs of night
Mark the beginning of spring
“Vernal equinox”
March 21st
Fall Equinox
Mark the beginning of fall
“Autumnal Equinox”
September 22nd
SOUTHERN HEMISPHERE
the seasons are reversed
Spring equinox is September 22nd
Fall equinox is March 21st
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32. The interactions of forces and materials on the planet.
The Earth System
The interactions of forces and materials on the planet.
Contains four parts;
Atmosphere: Layer of gases- the air- that surrounds earth
Lithosphere
Hydrosphere
Biosphere
Gases include;
Nitrogen
Oxygen
Carbon dioxide
The atmosphere also contains:
OZONE: A form of oxygen in the atmosphere that helps
protect Earth from harmful solar radiation.
definition
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33. “Solstice and Equinox”
Summary
Here you see the Earth rotating on its axis, and also revolving around the sun.
The solstices & equinoxes will briefly flash on the screen for each time of year
“Solstice and Equinox”
Click here for a GREAT interactive
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34. The End

35. Earth spins around its axis as it orbits the Sun.
Websites to visit:
Earth spins around its axis as it orbits the Sun.
Our entire Solar System slowly orbits around the Milky Way Galaxy.
The Milky Way Galaxy belongs to the Local Group of galaxies,
where it is also moving.
Click here for an interactive activity on Seasons
Click here for an excellent video on Seasons
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36. SOLAR SYSTEM definition
definition
SOLAR SYSTEM
The Sun and the objects that move about it, including planets, moons, and asteroids.

37. June 21st
Back
Summer Solstice

38. Winter Solstice Solstice
definition
Solstice
The days when the Sun’s vertical rays are farthest from the equator
December 21st
Back
Winter Solstice

39. Tropic of Cancer definition
line of latitude north of the equator

40. Tropic of Capricorn definition
line of latitude south of the equator

41. definition
ARCTIC CIRCLE
line of latitude 66.5˚
north of the equator

42. ANTARCTIC CIRCLE definition
line of latitude 66.5˚ south of the equator

43. Middle Latitudes ARCTIC CIRCLE TROPIC OF CANCER TROPIC OF CAPRICORN
ANTARCTIC CIRCLE
Middle Latitudes

44. Next ANIMATION ROTATION

45. Aurora over Edmonton, Alberta