April 24, 2012
The diagram models Earth and the moon in two
positions of its orbit. The arrows indicate the direction
of light from the sun.
In your Answer Document,
identify what phase of the moon
will be seen from Earth when the
moon is in position X. Describe or
draw what that phase looks like
from Earth. Indicate in your
description or drawing what portion
of the moon is lit or is not lit.
Then, identify what phase of the
moon will be seen from Earth when
the moon is in position Z. Describe
or draw what that phase looks like
from Earth. Indicate in your
description or drawing what portion
of the moon is lit or is not lit. (4
points)
April 24, 2012
From Earth, the moon phase at
position X would be the third
quarter moon , and the left half
of the moon, as seen from a
position in the northern
hemisphere of Earth, would be
lit. The moon phase at position Z
is the new moon phase. At this
position, the moon would appear
completely dark.
April 24, 2012
Students observe that the length of the shadow of a flagpole
varies throughout the year. They measure and diagram the
flagpole’s shadow in spring, summer and fall at mid-afternoon.
The students’ diagrams are shown.
In your Answer Document, describe or draw what the
flagpole’s shadow will look like at mid-afternoon in the
winter, December 21.
Then, explain why the flagpole’s shadow length
changes throughout the year. (2 points)
April 24, 2012
The length of a shadow can be used to
determine the time of year at certain
locations on Earth. Since Earth is tilted, it
receives varying degrees of sunlight
throughout the year. This makes the sun
appear low or high in the sky, and affects
the length of shadows cast by objects on
Earth.
April 24, 2012
The sun is a mid-sized, main sequence
star.
What stage is next in the life cycle of the
sun?
A. Red Giant
B. Black Hole
C. White Dwarf
D. Neutron Star
April 24, 2012
A. red giant
The life cycle of a star
depends on its mass. For our
sun, a main sequence star,
the next stage is the red
giant stage
.
April 24, 2012
The diagrams show the sun, Earth and moon in
different positions relative to one another.
Which diagram shows the correct arrangement of
the sun (S), Earth (E) and moon (M) relative to the
location of high tides
C
A
B
D
April 24, 2012
B • High tides are caused by the
tidal interaction between the
moon and Earth. The
gravitational pull of the moon on
Earth is the cause of both tidal
bulges. Because the moon is so
close to Earth, the pull of the
moon changes very quickly over
very short distances. The bulge
on the side of Earth that is
opposite the moon is due to
significantly weaker force on the
oceans on that side of the
planet.
April 24, 2012
Which unit of measurement do
astronomers use when
measuring the distance
between two stars found in the
Milky Way?
April 24, 2012
light-year
A light-year is just under ten trillion
kilometers. Earth’s closest neighbor, Mars,
is over 78,000,000 kilometers away.
Scientists use the unit of light-years so that
they can use much smaller numbers to
show very great distances. For example,
the closest star to Earth is about four lightyears away. A light-year is the distance that
light travels in one year. Light travels at a
constant speed of 300,000,000 meters per
second in space. This means that light from
a galaxy that is one light-year away will
take one year to reach Earth
April 24, 2012
Two galaxies are interacting with
each other.
What is the force that draws these
two galaxies toward each other?
A. Friction
B. Gravity
C. Electricity
D. Magnetism
April 24, 2012
• Gravity is the force that holds people to
Earth and the planets in orbit around the
sun. On a larger scale, gravity is also the
force that holds stars, gas and dust
together, making a galaxy. The gravity of
this system of stars, gas and dust is strong
and can act over the extremely large
distances between galaxies.
April 24, 2012
What causes the streak of
light observed when a
meteoroid enters Earth’s
atmosphere?
A. sunlight reflected from the meteoroid
surface
B. energy released from radioactive materials
in the meteoroid
C. lightening produced between the meteoroid
and the upper atmosphere
D. visible light produced from the interaction
between the meteoroid and the upper
atmosphere
April 24, 2012
D. The meteoroid enters Earth’s
atmosphere at a very high speed. The
visible light is a result of heat produced by
ram pressure. As the meteor swiftly moves
through the atmosphere, the meteoroid
compresses the air in it. The compression
heats the air, which in turn heats the
meteoroid. The intense heat vaporizes
most meteoroids, creating the meteor event
(or “shooting star”).
April 24, 2012
Which diagram
shows a Full
Moon?! Circle the
correct answer.
April 24, 2012
April 24, 2012
Question 37
Why do satellites and spacecraft
launched from Earth need to reach a
specific speed to escape Earth’s
surface?
• A. to overcome Earth’s
gravitational force
• B. to protect equipment from
radiation
• C. to break through the sound
barrier
• D. to avoid Earth’s magnetic field
April 24, 2012
A. to overcome Earth’s
gravitational force
Satellites and spacecraft have
to travel at a certain speed
(about 11 km/s) to overcome the
pull of Earth’s gravity (pulling
force Earth exerts or puts on
objects). If the object can’t go
that fast, it will fall back to
Earth’s surface.
April 24, 2012
This photograph of Galaxy M-82 was taken
by students at the Kitt Peak observatory in
Arizona.
Which type of equipment did the students use to
collect the light to make this photograph?
• A. satellite
• B. binoculars
• C. microscope
• D. optical telescope
April 24, 2012
D. optical telescope
An optical telescope is used to
collect the light needed to make
photographs of galaxies like this
one.
April 24, 2012
Question 42
Which phenomena occur
as a result of the
gravitational attraction
between the moon and
Earth?
• A. eclipses
• B. ocean tides
• C. seasonal changes
• D. phases of the moon
April 24, 2012
B. ocean tides
The gravitational pull of the moon on Earth
(and its oceans) causes the tidal bulge that
is responsible for ocean tides on Earth.
April 24, 2012
Question 44
What change would occur
if Earth’s rate of rotation
significantly increased?
• A. The year would be
shorter.
• B. The year would be
longer.
• C. The day would be
shorter.
• D. The day would be
longer.
April 24, 2012
C. The day would be shorter.
If Earth began to spin faster it would take
less time than it did before for Earth to make
one complete rotation. Because one rotation
of Earth is equal to the length of a day, days
would become shorter as a result of the
faster rotation rate. Each full rotation that
Earth makes is equal to one day, so the
faster that Earth spun, the shorter the days
would become.
April 24, 2012
Fossils of the Coelacanth (sØ' lŒkanth') fish occur in the fossil record from
410 to 65 million years ago. The lack of more recent fossils led scientists to
conclude that the fish went extinct along with the dinosaurs. In 1938, a
fisherman caught a living Coelacanth. More than 200 of them have been
caught on the deep reefs in the Indian Ocean. This fish has been called a
“living fossil” because its body plan is nearly identical to the 400-million-yearold fossils.
This structural similarity, as evidenced by the fossil record, supports which
statement?
• A. The environment of the deep sea has changed little over millions of
years.
• B. The amount of salt in the deep sea has varied greatly over millions
of years.
• C. The oceans have completely dried up multiple times during the past
400 million years.
• D. The oceans have been continuously repopulated by freshwater fish
species over millions of years.
April 24, 2012
A. The environment of the deep sea has
changed little over millions of years.
A big change in the environment will mean
that the characteristics of a population that
helped the species stay alive in one
environment may not help it stay alive in
another environment. This will cause the
population to become extinct (no more of
this species on planet Earth), or develop
new characteristics (adapt). Since the
fossil record shows that this type of fish did
not change in millions of years, the
environment that it lives in most likely did
not experience any major changes.