The Solar System Planets & their sizes http://www.rense.com/general72/size.htm Planets & their sizes

The Planets Mercury, Venus, Earth, and Mars Inner planets – nearest to the sun Terrestrial planets – have solid, rocky crusts Jupiter, Saturn, Uranus, Neptune Outer planets – farthest from sun Gas Giant Planets – more gaseous & less dense Largest – Jupiter Smallest – was Pluto, now Mercury Earth is the 5th largest

Terrestrial/Gas Giant Mercury Inner 3,032 mi Zero Planet Inner or Outer? Size # of Moons Terrestrial/Gas Giant Mercury Inner 3,032 mi Zero Terrestrial – scalding hot Venus 7,521 mi Earth 3rd planet from the sun - about 93 million miles away 7,926 mi One Terrestrial – has liquid water at the surface and can support varieties of life

Terrestrial/ Gas Giant Planet Inner or Outer? Size # of Moons Terrestrial/ Gas Giant Mars Inner 4,218 mi Two Terrestrial – cold, barren desert Jupiter Outer Largest - 88,694 mi 62 Gas Giant Saturn 74,586 mi 33 Uranus 31,784 mi 27 Neptune 30,832 mi 13

Asteroids, Comets, Meteoroids Asteroids: small, irregularly shaped, planetlike objects; mainly found between Mars and Jupiter in asteroid belt; a few follow paths that cross the Earth’s orbit Comets: made of icy dust particles and frozen gases; look like bright balls with long, feathery tails Meteoroids: pieces of space debris

Water, Land, and Air Oceans, lakes, rivers, and other bodies of water make up the Hydrosphere About 70% of our earth is water

Water, Land, and Air Lithosphere - Land makes up the part of this earth - includes the ocean basins (land beneath the oceans)

Water, Land, and Air Atmosphere ~ The air we breathe - 6,000 miles above earth’s surface

Water, Land, and Air Biosphere: part of earth that supports life

Reflection With a person reflect on the following: What is the hydrosphere? What is the atmosphere? What is the lithosphere? What is the biosphere?

Earth Notes Chapter 2 ~ Section 2 Forces of Change

The Earth’s Interior Inner Core – about 4,000 miles below the surface of the Earth Outer Core – 1,400 miles thick, temperature reaches 8500°F

Earth’s Interior (con’t) Mantle: layer of hot, dense rock – MAGMA

Earth’s Interior (con’t) Crust: rocky shell forming Earth’s surface. The crust is broken into slabs of rock called plates. Natural forces interact with the crust, creating landforms on the surface of the earth. Below the oceans, the crust is about 5 miles thick. Below the continents it averages 22 miles in thickness.

Earth’s Interior (con’t) Plates - float on a melted layer in the upper mantle - carry the earth’s oceans and continents

Reflection Describe the inner layers of the Earth with your partner.

Internal Forces of Change

The Plate Tectonic Theory The lithosphere — the earth’s crust and upper layer of the mantle — is broken into a number of large, moving plates.

The Plate Tectonic Theory The plates slide very slowly over a hot, pliable layer of mantle. The earth’s oceans and continents ride atop of the plates. It’s along the plate boundaries that most earthquakes and volcanoes occur due to friction and pressure that produces heat.

Plate Movement Plate movement: creates oceans and mountain ranges

Plate Movement Continental Drift: the theory that the continents were once joined and then slowly drifted apart

Plate Movement Pangaea: gigantic super continent which eventually broke apart

Reflection What was Pangea? What caused it to divide? Based on Plate Tectonics? What do you think will happen to the planet’s continents in a few million years?

Ring of Fire A circle of volcanic mountains surrounding the Pacific Ocean It is one of the most earthquake-prone & volcano-prone areas on the planet. Hot Spots are hot regions deep within the mantle that produce magma, which rises to the surface. Volcanic island chains form as oceanic plates drift over the hot spot. Example: Hawaiian Islands http://www.classzone.com/books/earth_science/terc/content/visualizations/es0904/es0904page01.cfm?chapter_no=visualization

What Happens When Plates Meet? Nice to meet you!

When they meet, friction locks them into place for a long period, allowing pressure to build below the crust. When pressure is too great, they move with tremendous energy.

Volcanoes Form when magma inside the earth breaks through the crust. Lava flows and may produce a large, cone-shaped mountain They often form along plate boundaries Magma splits the earth’s surface when plates collide

Fault—a break in the earth’s crust Fault—a break in the earth’s crust. Movement along a fault can send out shock waves, causing an earthquake.

San Andreas Fault

San Andreas Fault

A devastating fire followed the 1906 earthquake in San Francisco

The San Fernando earthquake of 1971 collapsed freeway overpasses in southern California

Converging/Collision Zone Plates collide and push slowly against each other and form a collision or converging zone. If 2 oceanic plates collide, 1 slides under the other. Islands often form this way. If 2 continental plates collide, mountains are formed. Example: Himalayas

Continental Crush / Collide

Spreading Zone Plates pull away from each other and form a spreading zone. These areas are likely to have earthquakes, volcanoes, and rift valleys (a large split along the crest of a mountain). http://www.classzone.com/books/earth_science/terc/content/visualizations/es0804/es0804page01.cfm?chapter_no=visualization

Spreading Zone

Subduction They meet, or CONVERGE and form a subduction zone. *If an oceanic plate collides with a continental plate, the heavier oceanic plate will slide under the lighter, continental plate. This results in volcanic mountain building and earthquakes.

Subduction

Accretion Oceanic plates slide under continental plates and scrape off seamounts, leaving debris that causes the continents to grow outward.

Reflection Explain the difference between the following: Converging Subduction Accretion

External Forces of Change

External Forces What other forces can create landforms? Weathering – a process that breaks down rock at or near the surface into smaller pieces. - This is a VERY slow process – thousands to millions of years. Mechanical (or Physical) Weathering occurs when rock freezes – it can cause Frost Wedging, a crack in the rock caused by freezing.

alters the rock’s chemical makeup by changing the Chemical Weathering – alters the rock’s chemical makeup by changing the minerals. This can actually change one kind of rock into another. Important forces in Chemical Weathering are moisture and carbon dioxide. Through this process caves are created. Acid Rain causes another type of chemical weathering that destroys forests, pollutes water and kills wildlife.

Over thousands of years, areas with limestone rocks can develop caves. Groundwater dissolves a network of tunnels in the rock. If the water table is lowered by a change in climate or tectonic uplift of the area, groundwater drains out of the tunnels, leaving the caverns exposed to air. http://www.classzone.com/books/earth_science/terc/content/visualizations/es1405/es1405page01.cfm?chapter_no=visualization

EROSION Erosion is the movement of weathered materials including gravel, soil and sand. The most common agents of erosion are water, wind and glaciers.

WATER AND EROSION Moving Water (rain, rivers, streams and oceans) is the greatest agent of erosion. Sediment – small particles of soil, sand, and gravel - is carried by the moving water and works like sandpaper to grind away rocks.

Erosion Sullivan Falls Rickett’s Glen State Park Pennsylvania

Sediment Sediment from the River Rhône flowing into Lake Geneva.

Sediment http://www.classzone.com/books/earth_science/terc/content/visualizations/es0604/es0604page01.cfm?chapter_no=visualization

Sediment creates new landforms such as floodplains & deltas. Deltas form at the mouth of a river

Wind Erosion The second major cause of erosion is wind, especially where there is little water and few plants. Wind Erosion can devastate one area while benefiting another – HOW? Loess – windblown deposits of mineral-rich dust

GLACIERS CAUSE EROSION? Glaciers are slow moving sheets of ice that are formed over many years.

GLACIERS How do they cause erosion? The movement cuts through land creating lakes. They melt away and then rebuild again over thousands of years.