1. The Earth

2. Planet Earth

3. Our Solar System The Planets: Neighbors in Space At least 9 exist
Mercury, Venus, Earth, & Mars are closest to the sun
Earth is about 93 million miles from the sun
Earth is 3rd planet from the sun
Farthest from the sun are Jupiter, Saturn, Uranus, Neptune, and Pluto
Jupiter is the largest
Earth ranks 5th in size
Pluto is the smallest

4. Solar System (cont.) Asteroids, Comets, and Meteoroids
Asteroids are small, irregularly shaped objects
Comets are made of icy dust particles and frozen gases (have tails)
Meteoroids are pieces of space debris
Chunks of rock and iron

5. Getting to Know Earth Earth is not a perfect sphere
Its wider around the center than from top to bottom
The difference is less than 1%
Water, Land, and Air
About 70% of the earth’s surface is water – hydrosphere
About 30% is land – lithosphere
Air we breathe (78% nitrogen, 21% oxygen, 1% other) – atmosphere
People, animals, & plants that live on the earth - biosphere

6. Getting to Know Earth (cont.)
Landforms
Seven Continents – be able to name these!
The part of the continent that extends under water – continental shelf

7. Getting to Know Earth (cont.)
Earth’s Heights & Depths
Highest Point – Mt. Everest (South Asia) – 29,035ft
Lowest dry land point – Shore of the Dead Sea (Southwest Asia) – 1,349ft below sea level
Deepest Depression (under the sea) – Mariana Trench (southwest of Guam) – 35,827ft deep

8. Forces of Change

9. Earth’s Structure A Layered Planet Three Layers
Core (Inner & Outer), Mantle, Crust

10. Earth’s Structure (Cont.)
Plate Movement
Many scientists believe that in the past, there was one giant super continent called Pangaea
Over millions of years, it broke apart into smaller continents that we know today
We will watch the video “Catastrophic Past”

11. Earth’s Structure (Cont.)
The earth’s plates continue to move and cause change, as well as natural disasters
Push-up mountains, create volcanoes, & produce earthquakes
Plate Tectonics

12. Internal Forces of Change
Colliding & Spreading Plates
Folds & Faults – know the difference

13. Internal Forces of Change (Cont.)
Earthquakes
Ring of Fire – Pacific Ocean – most earthquake-prone areas on the planet
Volcanic Eruption
Also occurs along the Ring of Fire

14. External Forces of Change
Weathering
Break down of rocks into smaller pieces
Wind Erosion
Movement of dust, sand, & soil
Glacial Erosion
Water Erosion
From rain, rivers, streams, & oceans

15. Earth’s Water

16. Water Cycle 4 Stages Evaporation Condensation Precipitation
Run-off/Groundwater
Although these stages work in a continuous motion, please learn them in this order!

17. Bodies of Salt Water Oceans Seas, Gulfs, and Bays
About 97% of the earth’s water is found in the oceans!
4 Oceans – Know These!
Seas, Gulfs, and Bays
Ocean Water to Drinking Water
97% of the world’s water is too salty for us to use
Desalination is the process of removing salt from the water so we can use it.

18. Bodies of Freshwater 3% of the earth’s water is freshwater
2% (of this 3) is frozen in glaciers
Another .5% is underground
What does that leave us?
Lakes, Streams, and Rivers
Groundwater
Important source of water (sometimes found in wells)