Warm-Up # 46

What is a galaxy?

millions or billions of stars, gas and dust, held together by gravitational attraction

What have many irregular shaped galaxies been involved in?

• COLLISION with Another galaxy

WARM-UP #47

1)1) Background radiation. This radiation, a type of Background radiation. This radiation, a type of energy, is believed to be left over from the energy, is believed to be left over from the actual Big Bang. actual Big Bang.

2)2) The expansion of the universe. This means the The expansion of the universe. This means the distance between galaxies is increasing over distance between galaxies is increasing over time.time.

Warm-Up # 48Warm-Up # 48What evidence is there for the What evidence is there for the

Big Bang Theory???Big Bang Theory???

How old is the universe?

WARM-UP #50

The first man made object ever sent into space was

in 1957 when the Russian satellite named Sputnik was launched.

WARM-UP #49

ABOUT 14 BILLION YEARSABOUT 14 BILLION YEARS

Warm-Up # 50Warm-Up # 50How old is the universe?How old is the universe?

Why are the spectra of galaxies shifted toward the red end?

They show redshift because they are moving away from us.

WARM-UP #51

WARM-UP # 52

What is ONE piece of evidence that the continents were once all

joined together?

You know two – fit together like a puzzle and matching fossil evidence.

WARM Up # 53Who proposed the theory of

continental drift?

Alfred Wegener proposed the

theory of continental drift

in 1912. He was a German scientist.

What is the theory of seafloor spreading and what scientist developed this theory?

Warm-Up # 54

Scientists found that the youngest rocks are located at the mid-ocean ridges. It was discovered by Henry Hess.

Warm-Up # 56

Seafloor spreading (Hess) and continental

drift (Wegner)

What are the two theories that when combined make up the theory of plate tectonics?

Warm-Up # 55

Label the three major layers of earth on this diagram:

Warm-Up # 57A. What theory of explains why the seafloor has both trenches and mid-ocean ridges?

B. Evidence that tectonic plates are being created at divergent boundaries is that _______ rocks are found at the mid-ocean ridges and ______________rocks are found further away.

C. What is the name of the one large supercontinent that existed millions of years ago?

Seafloor spreading

younger

older

Pangea

Warm-Up # 58Warm-Up # 58

What is the name of the most famous transform fault (plate boundary) in

the world? San Andreas Where is it?California

What is a transform fault?

A plate boundary where the plates grind past each other (not toward or away

from each other).

February 20Warm-Up # 59

What is hot, melted rock under the surface of the

Earth known as???

MAGMA. Hot, melted rock on the surface of

Earth is known as LAVA

February 20Warm-Up # 60

What are climate clues????

Wegner found fossils of the same organism but in very different climates – like a tropical

plant in a polar region or a glacial (glacier) deposit in a tropical region.

Warm-UP # 61

Two plates in California form a transform fault. The Pacific Plate

moves toward the North American

Plate causing earthquakes

along the fault.

Why are there so many

earthquakes in California?

18

WARM-UP # 62Which earthquake wave travels the slowest?

Primary Waves (p-waves) are the slowest.Which earthquake wave is the most destructive?

Surface/Land Waves (L-waves are the most destructive.

19

WARM-UP # 63What scale is used to compare the strengths of

earthquakes ? The Richter magnitude scale is used to describe the strength of an earthquake and is based on

the height of the lines on the seismogram.

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WARM-UP # 64What is the difference between the focus of an

earthquake and the epicenter of an earthquake?The focus is UNDERGROUND. It is the place on the Earth’s crust where the pressure was released.

The Epicenter is the spot on the Earth’s surface directly above the focus.