Download Grade 8 Earth/Space Pretest

Grade 8 Earth/Space Pretest
Select the best answer to each question.
____
1. Scientists use the light-year to describe the relationships between objects in space. What does a light-year
measure?
A. the distance that light can travel in one year
B. the brightness of light that travels through space
C. the number of years it takes light to travel to Earth
D. the time it takes light to travel 1 million km
____
2. The table shows distances between two objects or places in kilometers. Kilometers, however, are not the units
that scientists usually use to measure all the distances shown in the table.
DISTANCES BETWEEN OBJECTS OR PLACES
Two objects or places
Distance in kilometers
Boston and Los Angeles
More than 4,000 km
Earth’s maximum distance from Saturn
About 1.2 billion km
The Sun and the nearest star
About 40 trillion km
Earth’s surface and an orbiting satellite
About 400 km
The distance between which two objects or places would best be measured in light years?
A. Boston and Los Angeles
B. Our Sun and the nearest star
C. Earth’s maximum distance from Saturn
D. Earth’s surface and an orbiting satellite
____
3. All electromagnetic waves travel across space at the speed of light, 9.46 trillion kilometers per year. Visible
light and radio waves are both electromagnetic waves. Imagine that an interstellar probe could travel 9.46
trillion kilometers out in space. The probe sends radio signals back to Earth so that ground controllers can
track it. Which length of time would it take radio signals from the probe to reach radio receivers on Earth?
A. one year
B. six months
C. 9.46 years
D. 9.46 trillion years
____
4. In 1995, the Hubble Space Telescope photographed a tiny spot in the sky for a period of ten days; 342
exposures were placed together to create an image known as the Hubble Deep Field. Although the sample is
tiny, it is representative of the universe, which looks similar in all directions. The image below shows a
collection of billions of stars. The Hubble Deep Field shows at least 3,000 groups of these stars.
Which term describes this group of stars?
A. moon
B. galaxy
C. universe
D. solar system
____
5. Some astronomers study the universe and all the matter in it. They want to find out how big and how old the
universe is. Which statement provides the most accurate description of the universe?
A. The universe is a big collection of stars called the Milky Way.
B. The universe is all the stars that can be seen in the sky at night.
C. The universe is all the planets and stars that orbit around the Sun.
D. The universe is all of space and all the matter and energy that space contains.
____
6. Our Galaxy, the Milky Way, is a spiral galaxy containing many millions of stars. Spiral galaxies have rotating
arms made up of stars that extend from a central disk of densely packed stars. Which statement describes the
other two main types of galaxies?
A.
B.
C.
D.
Groups are big, round galaxies, and clusters are small, round galaxies.
Clusters are small, round galaxies, and superclusters are big, round galaxies.
Elliptical galaxies are oval shaped, and irregular galaxies have no particular shape.
Irregular galaxies are oval shaped, and elliptical galaxies have no particular shape.
____
7. Which group below correctly lists structures in space from smallest to largest?
A. star, planet, Milky Way, galaxy
B. planet, solar system, galaxy, star
C. moon, planet, solar system, galaxy,
D. galaxy, planet, Milky Way, solar system
____
8. The diagram shows the planets of our solar system, ranked according to relative size.
What is the planet that is closest in size to the Sun?
A. Earth
B. Jupiter
C. Saturn
D. Venus
____
9. One of the objects that astronomers study with telescopes on land and in orbit around Earth are called
nebulae. Which statement correctly describes what a nebula is and where in relation to other objects nebulae
may be found?
A. A nebula is an exploding star found in a galaxy.
B. A nebula is a type of galaxy found throughout the universe.
C. A nebula is a cloud of gas and dust found in interstellar space.
D. A nebula is a star in the universe that used up all of its nuclear fuel.
____ 10. Which of these choices states Newton’s law of universal gravitation?
A. As a planet moves around its orbit, the planet sweeps out equal areas in equal amounts of
time.
B. The orbit of a planet, or other body, around the sun is an ellipse, with the sun at one focus
of the ellipse.
C. The square of a planet’s orbital period is proportional to the cube of the planet’s mean
distance from the sun.
D. Gravitational force increases as the mass of an object increases or as the distance between
two objects decreases.
____ 11. Gravity is one of the fundamental forces in nature. It plays an important role in the formation of planets, stars,
galaxies, and solar systems. To explain gravity, English physicist Sir Isaac Newton in 1687 published his
Law of Universal Gravitation. Which statement gives the best overall definition of gravitation, or the force of
gravity, according to Newton’s law?
A. Gravitation is a force that makes the Earth rotate.
B. Gravitation is a force that makes the Sun so hot that it shines.
C. Gravitation is a force that pulls together all matter in the universe.
D. Gravitation is a force that keeps the Sun, planets, and other objects apart.
____ 12. The force of gravity has played a major role in the formation of the solar system. The diagram below shows
how the solar system most likely formed from a cloud of gas and dust (left) to create a swirling disk of matter
around a denser center (top left), that formed a star (center left) that was eventually surrounded by planets.
Which statement below best explains how gravity began the process that formed the solar system?
A. The planets formed from the gravity of gas and dust and held the Sun in place in the
center.
B. The cloud of gas and dust started to swirl because of gravity and formed the planets, which
broke apart and formed the Sun.
C. The force of its own gravity pulled the Sun into the center of the dust and gas cloud, which
then came together to form the planets.
D. The force of its own gravity pulled gas and dust toward the center of the cloud, the
swirling mass in the center became the Sun, and leftover matter around the Sun became
the planets.
____ 13. The table below compiles information about the distance of various stars from Earth, their apparent
magnitude, and their absolute magnitude.
Star
Sirius
Vega
Arcturus
Aldebaran
Rigel
Betelgeuse
Apparent Magnitude and Absolute Magnitude of Various Stars
Distance from Earth Apparent
Absolute Magnitude
(ly)
Magnitude
8.6
–1.46
1.4
25
0.03
0.6
34
–0.04
–0.3
60
0.85
–0.3
1,400
0.12
–8.1
1,400
0.50
–7.2
Which of the stars listed in the table above would look the brightest when observed from Earth?
A. Sirius
B. Rigel
C. Arcturus
D. Aldebaran
____ 14. Stars come in all sizes and colors. Each color and size indicates a particular kind of star. In terms of size and
temperature, which is the best description of a red dwarf?
A.
B.
C.
D.
a small, hot star
a large, hot star
a small, cool star
a medium-size cool star
____ 15. The physical size of stars vary. Stars can be thousands of times bigger than our Sun or much smaller.
Astronomers have developed a way to measure and express the size of a star. Which unit of measurement do
astronomers use to measure the size of stars?
A. Kelvins
B. light years
C. solar radius (radii)
D. Astronomical Units (AUs)
____ 16. The sun does not rotate in the same way Earth does. The sun has different periods of rotation at different
latitudes. The figure below shows the rotation of the sun.
Which arrow shows the part of the sun that rotates the fastest?
A.
B.
C.
D.
R
S
T
W
____ 17. Armando drew a diagram showing how energy is transferred from the hot center of the Sun to its surface by
two processes. Which two processes of energy transfer did Armando’s diagram show?
A.
B.
C.
D.
cooling and conduction
radiation and conduction
nuclear fission and nuclear fusion
energy production and energy transport
____ 18. Kai drew a diagram of the layers of the Sun’s atmosphere, which begins just beyond the convective zone.
What did Kai label the Sun’s topmost layer, extending millions of kilometers into space?
A.
B.
C.
D.
the corona
the photosphere
the radiative zone
the chromosphere
____ 19. A planet’s surface gravity influences the thickness of the atmosphere that surrounds the planet. The table
below shows the surface gravities of the terrestrial planets as a percentage of the surface gravity of Earth.
Planet
Surface gravity (% of Earth’s gravity)
Earth
Mars
Mercury
Venus
100
37
38
89
Based on their surface gravities, which terrestrial planets would have atmospheres that are the least thick?
A.
B.
C.
D.
Mars and Venus
Earth and Venus
Mars and Mercury
Earth and Mercury
____ 20. Earth is the third planet from the Sun and Venus is the second planet from the Sun. However, unlike Earth,
Venus has a thick, poisonous atmosphere and temperatures well over 400 ºC. Why do astronomers call Venus
Earth’s twin?
A. life can exist on Venus and on Earth
B. the planets are almost the same size
C. Venus, like Earth, is covered with oceans
D. Venus orbits more closely to Earth than any other planet
____ 21. Some planets, like Earth, still have active volcanoes or had active volcanoes in the past. The largest volcano
in the solar system is named Olympus Mons on Mars. Which statement best explains why Earth and some
other planets have volcanic mountains and others do not?
A. Some planets had mountains that over time turned into volcanoes.
B. Some planets collided with moons or other planets to melt rock that flowed along
channels and created volcanoes.
C. Some planets had many asteroids crash into the surface and blast out soil to make volcanic
craters in the tops of mountains.
D. Some planets are or were hot enough inside to melt rocks, which came to the surface and
flowed out as lava to form volcanic mountains.
____ 22. The diagram below shows several objects in space.
Which of these choices best identifies what the diagram shows?
A.
B.
C.
D.
location of comets
geocentric star system
heliocentric solar system
galaxy that is nearest to Earth
____ 23. For thousands of years, astronomers accepted the geocentric model as a good explanation of all the objects
they observed in the sky and the movements of those objects. Which statement best explains the basic
principles of the geocentric model?
A. The geocentric model shows the Earth at the center of the universe, with the Sun, planets,
and stars revolving around the Earth.
B. The geocentric model shows the Sun at the center of the universe, with Earth, the planets,
and the stars revolving around the Sun.
C. The geocentric model shows the Milky Way at the center of the universe, with Earth, the
planets, and the stars revolving around the Milky Way.
D. The geocentric model shows our solar system at the center of the Milky Way, with Earth,
the planets, and the stars revolving around our solar system..
____ 24. Both the geocentric and the early heliocentric models of the solar system viewed the planets as moving like
wheels within wheels. Johannes Kepler made an important finding that changed this view. Which statement
best explains how Kepler’s finding changed the heliocentric model?
A. Both models at first showed planets orbiting in perfect circles, but Kepler showed that the
orbits are ellipses.
B. Both models at first showed planets orbiting in ellipses, but Kepler showed that the orbits
are perfect circles.
C. Both models at first showed planets orbiting in ellipses, but Kepler showed that the orbits
orbit of Earth is a perfect circle.
D. Both models at first showed all the planets orbiting in perfect circles, but Kepler showed
that the orbit of Earth is an ellipse.
____ 25. During which two phases of the moon do neap tides take place?
A.
B.
C.
D.
new moon, full moon
new moon, first quarter moon
third quarter moon, full moon
first quarter moon, third quarter moon
____ 26. The diagram shows the Moon in its complete orbit around Earth over a period of about 29 days. The Moon
appears to have different shapes called phases.
Which phases occur at points 1 and 5, and what is causing the phases?
A. The new moon at point 1 and the full moon at point 5 are phases caused because the Moon
changes its shape from night to night.
B. The new moon at point 1 and the full moon at point 5 are phases when the Moon looks
like it is changing shape as Earth goes around the Moon.
C. The full moon at point 1 and the new moon at point 5 are phases caused because half of
the Moon is always lit by the Sun, but only part of the Moon’s lit surface can be seen as
the Moon orbits Earth and Earth orbits the Sun.
D. The new moon at point 1 and the full moon at point 5 are phases caused because half of
the Moon is always lit by the Sun, but only part of the Moon’s lit surface can be seen as
the Moon orbits Earth and Earth orbits the Sun.
____ 27. The moon viewed from Earth is mainly visible as a bright circle or part of a circle in the night sky. It can
sometimes appear as a faint object during the day. Which statement best explains why the Moon as seen from
Earth is a bright object?
A. The Moon is able to give off its own light.
B. The Moon is appears bright because it reflects light from Earth.
C. The Moon is appears bright because it reflects light from the Sun.
D. The Moon is appears bright because most Moon rocks are light colored.
____ 28. Radar sensors on high-altitude aircraft and on space platforms such as the space shuttle have been used to
produce three-dimensional maps of Earth’s surface. These radar sensors use electromagnetic wavelengths that
have the lowest energy. What type of electromagnetic radiation do these radar sensors use?
A.
B.
C.
D.
x-rays
ultraviolet
gamma rays
radio waves
____ 29. Ship captains, plane pilots, and motor vehicle drivers rely on the Global Positioning System to help them
navigate. The GPS network has 24 satellites in orbit around Earth. Look at the diagram of a part of the
system.
How does this arrangement of GPS satellites help people find out where they are and where they are going?
A. A receiver on Earth picks up signals from at least three GPS satellites, so that ship
captains, plane pilots, drivers, and hikers can call a phone number for directions.
B. A receiver gets a message from a GPS satellite tracking a vehicle and the satellite sends
information about maps back to the vehicle.
C. A receiver sends a message to a GPS satellite that a vehicle is lost and three satellites look
for the vehicle and report its location to the receiver.
D. A receiver on Earth picks up signals from at least three GPS satellites, and the technology
in the receivers can pinpoint the location of boats, airplanes, cars, and hikers and help
them find their way.
____ 30. Between 1967 and 2006, many uncrewed spacecraft visited Venus. Cameras took pictures of the planet’s
surface, and instruments sampled gases and took temperatures in the thick clouds that surround Venus. Which
type of spacecraft were those that explored Venus?
A. space probes
B. space shuttles
C. space capsules
D. planetary fly-bys
____ 31. The transfer of energy as electromagnetic waves is called radiation. Not all electromagnetic waves emit the
same radiation. What determines the radiation that an electromagnetic wave emits?
A. its speed
B. its visibility
C. its amplitude
D. its wavelength
____ 32. Old stars, young stars, gas clouds, and other objects far out in space give off different kinds of
electromagnetic waves, such as visible light, ultraviolet light, and x-rays. Astronomers study the different
kinds of waves to learn about the objects. All the waves are part of the electromagnetic spectrum, but
differences in one property create the different kinds of waves. Sasha drew a diagram of an electromagnetic
wave and labeled its parts.
Which property of the wave that Sasha label “W” determines what kind of electromagnetic wave it is?
A. crest
B. trough
C. amplitude
D. wavelength
____ 33. There are telescopes made to detect all kinds of electromagnetic waves so that images can be created from the
data they collect. For example, radio telescopes detect radio waves and x-ray telescopes detect x-rays. What
type of electromagnetic radiation do optical telescopes detect?
A. visible light
B. microwaves
C. infrared light
D. ultraviolet light
____ 34. How does the aerospace industry affect Florida’s economy?
A.
B.
C.
D.
increases taxes for Floridians
puts stress on Florida’s resources
consumes the state’s monetary resources
provides jobs for thousands of Floridians
____ 35. Suppose that NASA had to cut back greatly on some aerospace programs and even cancel others. The laid-off
workers would have less money to spend. The darker areas on the map of Florida shows were the greatest
number of aerospace workers live.
As a result of NASA’s cutbacks, which part of Florida does the map show is likely to experience a drop in
automobile sales and in retail sales of all kinds?
A. Florida Panhandle
B. Florida’s Gulf coast
C. Florida’s central and south Atlantic coast
D. Florida’s southern tip and the Florida Keys
____ 36. NASA and Florida’s aerospace industry employs many thousands of engineers, researchers, scientists, and
other workers. Which of the following categories are NOT ways that the space program has brought revenue
to Florida?
A. launching of communications, weather, and global positioning system satellites by private
industry
B. increasing Florida tourism by attracting visitors to watch rocket launches and tour the
Kennedy Space Center
C. improving the local economy by encouraging the operation of hotels, restaurants, and
local shops to serve tourists and Florida residents alike
D. planting of more citrus groves throughout Florida to increase the available supply of
oranges, grapefruit, and lemons for shipping to Northern states
Grade 8 Earth/Space Pretest
Answer Section
MULTIPLE CHOICE
1. ANS: A
• A is correct because a light-year is the distance light can travel in one year.
• B is incorrect because a light-year is the distance light can travel in one year. It is not a measure of the
brightness of light.
• C is incorrect because a light-year is the distance light can travel in one year, not the number of years it
takes light to travel to Earth.
• D is incorrect because a light-year is a measure of distance, not time.
STA: SC.8.E.5.1
2. ANS: B
A is incorrect because distances on Earth are usually measured in kilometers.
B is correct because astronomers measure distances in interstellar space in light years.
C is incorrect because astronomers use Astronomical Units rather than kilometers to measure and express
distances in the solar system.
D is incorrect because the altitude of satellites above Earth is usually expressed in kilometers.
STA: SC.8.E.5.1
3. ANS: A
A is correct because 9.46 trillion kilometers is the distance that light or radio waves would travel in a year.
B is incorrect because 4.73 trillion kilometers is one half the distance that light or radio waves would travel in
a year, which means the waves would travel this distance in six months.
C is incorrect because light travels 9.46 trillion kilometers in one year, and so could travel 9.46 times that
distance in 9.46 years.
D is incorrect because 9.46 trillion is the number of kilometers that light and radio waves travel in a year, and
it would not be possible for ground controllers to track a the probe over 9.46 trillion years.
STA: SC.8.E.5.1
4. ANS: B
• A is incorrect because a galaxy, not a moon, is a collection of stars. A moon is a natural satellite that
revolves around a planet.
• B is correct because galaxies are groups of millions or billions of stars held together by their own gravity.
• C is incorrect because a galaxy, not the universe, is a collection of millions or billions of stars. The universe
is made up of a very large number of galaxies.
• D is incorrect because a galaxy, not a solar system, is a collection of millions or billions of stars. A solar
system is made up of a star and the objects that orbit it.
STA: SC.8.E.5.2
5. ANS: D
A is incorrect because the Milky Way is only one galaxy among billions in the universe.
B is incorrect because the stars in the night sky are mainly in the Milky Way, but the universe contains may
more stars than just those in our galaxy.
C is incorrect because the planets in our solar system orbit the Sun, but other stars do not orbit the Sun.
D is correct because the universe contains more than our solar system and our galaxy, it contains all the
matter and energy in space.
STA: SC.8.E.5.2
6. ANS: C
A is incorrect because groups and clusters are not galaxies but collections of many galaxies.
B is incorrect because clusters and superclusters are not galaxies but groupings of many galaxies.
C is correct because oval-shaped elliptical galaxies and odd- shaped irregular galaxies are the other two
galaxies in addition to spiral galaxies.
D is incorrect because ellipical galaxies are oval shaped and irregular galaxies have no particular shape.
STA: SC.8.E.5.2
7. ANS: C
A is incorrect because a star is larger than a planet and the Milky Way is a galaxy.
B. is incorrect because a galaxy is a group of stars.
C is correct because a moon is smaller than a planet and a solar system is part of a galaxy.
D is incorrect because a galaxy is not smaller than a planet and the Milky Way is not smaller than a solar
system.
STA: SC.8.E.5.3
8. ANS: B
A is incorrect because the Sun is larger than any of the planets, thus it is closest in size to the largest planet,
Jupiter, not Earth, which is the fifth largest planet.
B is correct because the Sun is the only object in the solar system that is larger than Jupiter, the largest planet.
C is incorrect because the Sun is larger than any of the planets, thus it is closest in size to the largest planet,
Jupiter, and Saturn is the second largest planet after Jupiter.
D in incorrect because the Sun is larger than any of the planets, thus it is closest in size to the largest planet,
Jupiter, not Venus, which is close in size to Earth.
STA: SC.8.E.5.3
9. ANS: C
A is incorrect because an exploding star is called a supernova.
B is incorrect because a galaxy contains many stars and a nebula is a cloud of gas and dust.
C is correct because a nebula is a cloud of gas and dust found between the stars and from which new stars
form.
D is incorrect because stars that run out of fuel can become such dense objects as white dwarfs, neutron stars,
and even black holes.
STA: SC.8.E.5.3
10. ANS: D
A is incorrect because Kepler’s second law of planetary motion states that as a planet moves around its orbit,
the planet sweeps equal areas in equal amounts of time.
B is incorrect because Kepler’s first law of planetary motion states that the orbit of a planet or other body
around the sun is an ellipse, with the sun at one focus of the ellipse.
C is incorrect because Kepler’s third law of planetary motion states that the square of a planet’s orbital period
is proportional to the cube of the planet’s mean distance from the sun.
D is correct because Newton’s law of universal gravitation states that all objects in the universe attract one
another through gravitational force, and gravitational force increases as the mass of an object increases or as
the distance between two objects decreases.
STA: SC.8.E.5.4
11. ANS: C
A is incorrect because gravity is an attractive force, and gravity and Earth’s rotation are not related.
B is incorrect because nuclear reactions, not gravity, create enough heat in stars so that they shine.
C is correct because gravity is an attractive force between all objects that have mass.
D is incorrect because gravity attracts objects rather than keeps them apart.
STA: SC.8.E.5.4
12. ANS: D
A is incorrect because the Sun and not the planets formed first from the cloud of gas and dust.
B is incorrect because the Sun, not the planets, formed first and the planets did not break apart to form the
Sun.
C is incorrect because the Sun formed out of the gas and dust and did not exist apart from it.
D is correct because the gas and dust cloud collapsed under its own gravity, the Sun formed from the dense
material at the center, and the planets formed from the ring of leftover matter and were held in orbit by
gravity.
STA: SC.8.E.5.4
13. ANS: A
• A is correct because the star with the smallest apparent magnitude would appear to be the brightest.
• B is incorrect because stars with bigger apparent magnitudes are dimmer, and stars with smaller apparent
magnitudes are brighter.
• C is incorrect because Arcturus has a bigger apparent magnitude than Sirius, which makes Arcturus appear
dimmer from Earth than Sirius.
• D is incorrect because stars with bigger apparent magnitudes are dimmer, and stars with smaller apparent
magnitudes are brighter.
STA: SC.8.E.5.5
14. ANS: C
A is incorrect because red stars have cooler temperatures.
B is incorrect because a dwarf star is small and a red star is cool.
C is correct because a dwarf star is small and a red star is cool.
D is incorrect because a dwarf star is small, not medium in size.
STA: SC.8.E.5.5
15. ANS: C
A is incorrect because Kelvin is a temperature scale that scientists use to measure temperatures as hot as those
in stars.
B is incorrect because light years are a measure of the distance that light travels in a vacuum in one year.
C is correct because astronomers compare the size of stars with the size of the Sun and measure them
according to the Sun’s radius.
D is incorrect because AUs are a measurement of the distance from Earth to the Sun and are used to measure
distances in the solar system.
STA: SC.8.E.5.5
16. ANS: C
A is incorrect because the sun’s poles rotate slower (about 36 days) than the equator (about 26 days).
B is incorrect because the sun’s poles rotate slower (about 36 days) than the equator (about 26 days).
C is correct because the sun’s equator rotates faster (about 26 days) than the poles (about 36 days).
D is incorrect because the sun’s poles rotate slower (about 36 days) than the equator (about 26 days).
STA: SC.8.E.5.6
17. ANS: B
A is incorrect because the transfer of energy form the Sun’s core involves heating and conduction, not
cooling.
B is correct because energy travels by radiation through the radiative zone and by conduction in bubbling
cells through the conductive zone.
C is incorrect because nuclear fusion produces the Sun’s energy in the core.
D is incorrect because the answer does not tell how energy is transported.
STA: SC.8.E.5.6
18. ANS: A
A is correct because the corona is the top layer of the Sun’s atmosphere, where much solar activity goes on.
B is incorrect because the photosphere is the lowest level of the Sun’s atmosphere.
C is incorrect because the radiative zone is deep inside the Sun, between the core and the conductive zone.
D is incorrect because the chromosphere is the layer of the atmosphere below the corona.
STA: SC.8.E.5.6
19. ANS: C
A is incorrect because Venus has the thickest atmosphere of the terrestrial planets.
B is incorrect because Earth and Venus have the greatest surface gravities and the thickest atmospheres of the
terrestrial planets.
C is correct because Mars and Mercury have the lowest surface gravities and the thinnest atmospheres of the
terrestrial planets.
D is incorrect because Earth has the greatest surface gravity and Earth’s atmosphere is quite thick, although
not as thick as the atmosphere of Venus.
STA: SC.8.E.5.7
20. ANS: B
A is incorrect because it is not likely that life could exist in the hot, poisonous environment of Venus.
B is correct because Venus is only slightly smaller than Earth.
C is incorrect because there is no liquid water in Venus, which is so hot that water would boil away.
D is incorrect because the sizes, not the orbits, are why Venus is called Earth’s twin.
STA: SC.8.E.5.7
21. ANS: D
A is incorrect because volcanoes deposit molten rock to build up into mountain-size and shape.
B is incorrect because volcanic mountains are created by molten rock inside a planet that flow out.
C is incorrect because craters caused by asteroids or other bodies striking Earth are dug out, while craters in
volcanic mountains are like pipes from which molten rock flows.
D is correct because planets with interiors hot enough to melt rocks are the planets that have volcanic
mountains.
STA: SC.8.E.5.7
22. ANS: C
A is incorrect because the diagram shows the asteroid belt, planets, and the sun. It does not show comets.
B is incorrect because the sun is at the center, so the diagram shows our Solar System.
C is correct because the diagram shows the sun and the bodies that travel around it.
D is incorrect because the diagram is of our Solar System, not a galaxy.
STA: SC.8.E.5.8
23. ANS: A
A is correct because the ancient Greeks developed the geocentric, or Earth-centered, model, it was perfected
by the Greek astronomer Ptolomy, and astronomers accepted it until the 1600s.
B is incorrect because the geocentric model shows Earth, not the Sun, as at being at the center of the solar
system and the universe.
C is incorrect because the geocentric model was developed long before astronomers discovered that the Milky
Way was a galaxy filled with stars.
D is incorrect because astronomers did not then know about galaxies such as the Milky Way.
STA: SC.8.E.5.8
24. ANS: A
A is correct because both Ptolemy and Copernicus believed that the orbits of bodies in the solar system had to
be perfect circles, but Kepler showed that they are ellipses.
B is incorrect because neither Ptolemy nor Copernicus thought that the orbits were ellipses, but Kepler
calculated that they were ellipses.
C is incorrect because the early models showed the orbits as perfect circles, and Kepler showed that the orbits
of all the planets, not just Earth, were ellipses.
D is incorrect because Kepler showed that the orbits of all the planets, not just Earth, were ellipses.
STA: SC.8.E.5.8
25. ANS: D
A is incorrect because neap tides take place when the sun, the moon, and Earth form a right angle. During the
new moon and full moon phases, the three bodies form a straight line.
B is incorrect because neap tides take place when the sun, the moon, and Earth form a right angle. During the
first-quarter moon phase, the moon, the sun, and Earth form a right angle. However, in the new moon phase,
the three bodies form a straight line.
C is incorrect because neap tides take place when the sun, the moon, and Earth form a right angle. During the
third-quarter moon phase, the moon, the sun, and Earth form a right angle. However, during the full moon
phase, the three bodies form a straight line.
D is correct because neap tides take place when the sun, the moon, and Earth form a right angle, which
happens during the first-quarter moon and third-quarter moon phases. Under these conditions, the
gravitational effects of the sun and moon on Earth do not add together as they do in spring tides.
STA: SC.8.E.5.9
26. ANS: D
A is incorrect because the Moon does not change its shape. The amount of reflected sunlight from the Moon
changes.
B is incorrect because Earth does not orbit the Moon, the Moon orbits Earth.
C is incorrect because the phase at point 1 is not a full moon, instead it is a new moon.
D is correct because the phase at point 1 is a new moon when none of the Sun’s reflected light can be seen
from Earth. Point 5 is a full moon, when sunlight reflected from half of the Moon’s surface appears as a circle
in the sky.
STA: SC.8.E.5.9
27. ANS: C
A is incorrect because only stars give off their own light, all other bodies reflect light.
B is incorrect because the Moon does not reflect light from Earth, it reflects light from the Sun.
C is correct because the Moon reflects light from the Sun, which is a star that gives off light.
D is incorrect because the Moon reflects light from the Sun and so appears bright in the sky.
STA: SC.8.E.5.9
28. ANS: D
• A is incorrect because x-rays have very high energy.
• B is incorrect because infrared waves have an energy level just below that of visible light waves.
• C is incorrect because gamma rays have the highest energy.
• D is correct because radio waves have the lowest energy.
STA: SC.8.E.5.10
29. ANS: D
A is incorrect because the users of the GPS do not have to call for information; it is sent to their navigation
systems.
B is incorrect because at least three satellites must send information to a GPS receiver to track a ship, plane,
or motor vehicle.
C is incorrect because the system does not only track lost vehicles but tracks all vehicles that can connect to
the GPS system.
D is correct because at least three GPS satellites are needed to pinpoint a location and the technology in the
receiver provides communication with individual navigation systems.
STA: SC.8.E.5.10
30. ANS: A
A is correct because space probes are uncrewed craft that travel to another planet or body and collect
information that is transmitted back to Earth.
B is incorrect because space shuttles carry astronauts into Earth orbit and carry them back to Earth.
C is incorrect because space capsules atop large rockets carried astronauts into Earth orbit, then the capsule
parachuted down to land or splashed down in the ocean.
D is incorrect because fly-bys were done by spacecraft that just passed a celestial body and did not go into
orbit to gather information.
STA: SC.8.E.5.10
31. ANS: D
• A is incorrect because the wavelength, not its speed, determines the type of radiation that is emitted.
• B is incorrect because the wavelength, not its visibility, determines the type of radiation that is emitted.
• C is incorrect because the wavelength, not its amplitude, determines the type of radiation that is emitted.
• D is correct because the wavelength determines the types of radiation.
STA: SC.8.E.5.11
32. ANS: D
A is incorrect because the crest of the wave is the top, labeled S, but wavelength determines the kind of wave.
B is incorrect because the trough is the bottom part of the wave, labeled A, and this property does not
determine the kind of electromagnetic wave.
C is incorrect because amplitude is the maximum displacement of a wave from its resting point, labeled T,
but wavelength is the property that creates light waves, X-rays, and all other electromagnetic waves.
D is correct because wavelength is the length from one point, such as the crest, to the next crest, and
determines the nature of the electromagnetic wave.
STA: SC.8.E.5.11
33. ANS: A
A is correct because optical telescopes detect visible light.
B is incorrect because microwaves are so long that they are beyond human vision.
C is incorrect because infrared light has wavelengths too long for human eyes to see.
D is incorrect because ultraviolet has wavelengths too short for human eyes to see.
STA: SC.8.E.5.11
34. ANS: D
· A is incorrect because Florida invests billions of dollars in the space program, by which Floridians benefit.
· B is incorrect because Florida’s resources are not stressed. Instead, they are used in providing components
and materials used at the Space Center and for missions, which is economically beneficial to Florida.
· C is incorrect because Florida has invested billions of dollars in the space program, and the state is getting
many benefits for its investment. The money is not being thrown away, as the word consumes implies.
· D is correct because the aerospace industry provides thousands of jobs for Floridians, which is good for
Florida’s economy.
STA: SC.8.E.5.12
35. ANS: C
A is incorrect because the map shows few aerospace workers live in the Florida Panhandle, therefore NASA
cutbacks would not likely affect these workers and what they spend.
B is incorrect because relatively few aerospace workers live on the Gulf coast.
C is correct because the map shows that a great many aerospace workers live along the central and south
Atlantic coast.
D is incorrect because the map shows that fewer aerospace workers live in southern Florida and the Keys.
STA: SC.8.E.5.12
36. ANS: D
A is incorrect because private companies have been set up to launch various kinds of satellites and therefore
purchase materials and services and employ workers in this private launch business.
B is incorrect because thousands of tourists visit the space center each year.
C is incorrect because many hotel, restaurants, and other businesses were set up to serve all the tourists who
visit the space center each year.
D is correct because the businesses that grew as a result of the space center either supplied space-related
industries or the tourist industry, but were not connected with Florida’s citrus growers.
STA: SC.8.E.5.12