1. Atmosphere: the envelope of gases that surrounds the Earth.
Earth’s Spheres
Atmosphere: the envelope of gases that surrounds the Earth.

2. Earth’s Spheres
Hydrosphere: water part of the Earth, including surface and subsurface water.

3. Hydrosphere Refers to the watery part of the Earth.
Most of the Earth’s water is in oceans but also in lakes, streams rivers, groundwater and glaciers.

4. Hydrosphere
97% is salt water
The remaining 3% is fresh water, 2/3 of the total freshwater is frozen in the ice caps of the North and South Poles.

5. Hydrosphere
The hydrosphere also includes water found in the atmosphere and the amount tied up in the cycle.

6. Earth’s Spheres
Biosphere-Includes all living things on Earth

7. Earth’s Spheres
Lithosphere: outer solid shell of the Earth that extends 70 km or more from the crust and part of the Asthenoshere

8. Lithosphere Includes the earth’s crust and the upper mantle.
It is 100 km thick
The lithosphere is broken up into plates. They can move around independently of each other.
The plates float around on the asthenosphere, the liquid portion of the mantle.

9. Earth’s Spheres
Asthenosphere: partially melted layer of mantle below the lithosphere. This is responsible for plate tectonic movement.

10. 1. Crust: 10-65km thick A) Thickest under the continents.
B) Low density.
C) Lighter rock.
D) Solid.

11. 2. Mantle: The upper mantle contains magnesium, silicon, and iron.
A) 2900km ~ the thickest layer.
B) Made up of heavier rocks.
C) The upper mantle contains the Asthenoshere which is soft and flowing.

12. 3. Outer Core: the base of the mantle
A) Liquid iron and nickel.
B) 2175 km

13. 4. Inner Core: solid iron and nickel.
A) Spherical in shape.
B) km in diameter.

14. Atmosphere
The gaseous layer, extending from the surface of the earth to outer space.
It is made up of a mixture of gases with some suspended solids and liquids. The most common gases are
Nitrogen 78%
Oxygen 21%
1% water vapor and others

15. - The earth was NOT structured like this 4 billion years ago
- The earth was NOT structured like this 4 billion years ago. - According to the Protoplanet Hypothesis, the surface of the earth looked like the moon does. - The rock throughout the earth was same all the way through.

16. - As the earth heated, iron and nickel melted, flowed downward toward the center. On the way it melted lighter materials and forced them upward to the surface. - The lighter rock became solid and formed the crust.

17. Layers of the Atmosphere
The atmosphere filters ultraviolet rays and protects living things from the sun’s harmful UV rays.

18. 5 Layers of the Atmosphere
The layers become less dense (thick), the farther away from the Earth’s surface you go.

19. Troposphere 1. Troposphere – surface to 10 km (~6 miles) above.
Contains most of the gases
The air we breathe is here
Most weather occurs here.

20. Stratosphere 2. Stratosphere – 10km-45km (6-28 miles) above
The air is very thin here, but wind still blows.
Airplanes fly in the lowest parts
Contains the ozone layer, which protects us from the Sun’s UV rays.

21. Merge with Outer Space
3. Mesosphere
4. Thermosphere
5. Exosphere

23. “It’s often said that you cannot get something for nothing, but the universe may be the ultimate free lunch.” Alan Guth---physicist

24. How did the Earth Begin? meteroids,asteroids,comets
No scientist knows for certain how Earth was formed or from what it came.
There are a number of theories on the origin of earth.
All of these theories must consider the following scientific facts:

25. How did the Earth Begin?
A. All planets revolve around the sun in the same direction (counter clockwise)
B. The paths or orbits of planets are all nearly circular.
C. Orbits of planets are in nearly the same plane.
D. The sun rotates on its axis in almost the same plane as the planets

26. How did Earth Begin?
E. Most planets rotate in the same direction as the sun.
F. 6 planets have moons and most revolve around the planet as the planet does the sun.
G. The sun’s rate of rotation is slower than expected by scientists.

27. The Big 3 1. ENCOUNTER HYPOTHESIS
The Solar system began approximately 5 billion years ago with our sun already in existence.
The sun is hanging out when a star or perhaps a comet passes very close to the sun.

28. ENCOUNTER HYPOTHESIS
A collision happens and HUGE amounts of gas from the sun explode out of it but move in the same direction around the sun.
After a million years, the gases shrink into ball shaped bodies.
The larger ones become planets and the smaller ones become moons.
The ones that never shrank became comets.

29. NEBULAR HYPOTHESIS
A HUGE cloud of gas rotates through space, this cloud is called a nebular.
The nebula cools and shrinks, making it spin faster.
The spinning increases causing it to throw off a ring, then another until it has thrown off nine rings.
Each thrown ring becomes a planet.

30. NEBULAR HYPOTHESIS
The cloud at the center shrinks A LOT more. The shrinking causes compression which causes heating and it becomes a fiery HOT star.
The sun, planets and moons are all spinning in the same direction as the original nebula that they came from.

31. PROTOPLANET HYPOTHESIS
This is the theory most in favor right now.
The solar system began with a great cloud of gas and dust.
The cloud shrinks under the pull of its own gravitational force.
The material concentrates in the center where compression causes it to get really hot and it forms the sun.

32. PROTOPLANET HYPOTHESIS
Unlike the Nebular hypothesis, there are no rings.
10% of the cloud’s matter forms a single disk around the sun.
Both the disk and the sun rotate slowly.

33. PROTOPLANET HYPOTHESIS
Gravity within the disk causes material to collect in several huge whirlpools called eddies.
Write this on bottom of notes!
Eddies_beginning of sun formationplanetesimalsprotoplanetssun ignitesplanets and moons
There are some leftoverscomets, meteors asteroids, planetoids(large asteroids)
Link

34. How does the Earth evolve over time?
There are 3 theories on the evolution of the universe:
1. The Big Bang Theory
Proposed by Le Maitre and Gamnlow
In the beginning…
All matter in the universe was concentrated in an EXTREMELY dense and hot fireball.
20 billion years ago: a HUGE explosion occurred

35. The Big Bang Theory
All that matter was broken into pieces and thrown with high speed in all directions.
Eventually this formed stars and galaxies and these bodies are STILL moving away from each other.
As the matter cooled from the explosion, Hydrogen and Helium gas formed.
1 billion years later, the first stars were born.

36. 2. Steady State Theory Proposed by Bondi, Gold and Hoyle The theory:
The number of galaxies in the universe is constant and new galaxies are continuously created out of empty space when galaxies leave our universe.
The mass of the universe remains the same.

37. 3. Pulsating Theory
The universe is supposed to be expanding and contracting alternately…in other words pulsating
Right now it’s expanding.
The expansion is stopped by the pull of gravity and begins to contract again.
Once it reaches a certain size, an explosion would occur and the universe starts to expand again.