Warm-Up # 46
What is a galaxy?
millions or billions of stars, gas
and dust, held together by
gravitational attraction
WARM-UP #47
What have many irregular shaped
galaxies been involved in?
• COLLISION with
Another galaxy
Warm-Up # 48
What evidence is there for the
Big Bang Theory???
1) Background radiation. This radiation, a type of
energy, is believed to be left over from the
actual Big Bang.
2) The expansion of the universe. This means the
distance between galaxies is increasing over
time.
WARM-UP #50
How old is the universe?
WARM-UP #49
The first man made object ever
sent into space was
in 1957 when the Russian satellite
named Sputnik was launched.
Warm-Up # 50
How old is the universe?
ABOUT 14 BILLION YEARS
WARM-UP #51
Why are the spectra of galaxies
shifted toward the red end?
They show redshift because they are
moving away from us.
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 # 53
Who proposed the theory of
continental drift?
Alfred Wegener
proposed the
theory of
continental drift
in 1912. He was a
German scientist.
Warm-Up # 54
What is the theory of seafloor spreading
and what scientist developed this theory?
Scientists found that the youngest rocks
are located at the mid-ocean ridges. It
was discovered by Henry Hess.
Warm-Up # 56
What are the two theories that when combined
make up the theory of plate tectonics?
Seafloor spreading (Hess)
and continental drift
(Wegner)
Warm-Up # 55
Label the three major layers of earth on this diagram:
Warm-Up # 57
A. What theory of explains why the seafloor has
both trenches and mid-ocean ridges?
Seafloor spreading
B. Evidence that tectonic plates are being created
younger
at divergent boundaries is that
_______ rocks
are found at the mid-ocean ridges and
older
______________rocks
are found further away.
C. What is the name of the one large
supercontinent that existed millions of years
ago? Pangea
Warm-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 20
Warm-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 20
Warm-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
Why are there
so many
earthquakes in
California?
Two plates in
California form a
transform fault.
The Pacific Plate
moves toward the
North American
Plate causing
earthquakes along
the fault.
WARM-UP # 62
Which 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
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WARM-UP # 63
What 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 # 64
What 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.
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