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1)How long does it take Earth to complete one orbit around the Sun? 1) _______
A)one year
B)one month
C)one week
D)one day
E)The time varies significantly depending on the orbit. |
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2)Galileo challenged the idea that objects in the heavens were perfect by 2) _______
A)proving Kepler's laws were correct.
B)showing that heavy objects fall at the same rate as lighter objects.
C)inventing the telescope.
D)observing sunspots on the Sun and mountains on the Moon. |
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3)How did the Ptolemaic model explain the apparent retrograde motion of the planets? 3) _______
A)It held that the planets resided on giant spheres that sometimes turned clockwise and sometimes turned counterclockwise.
B)It held that sometimes the planets moved backwards along their circular orbits.
C)It held that this motion occurs as Earth passes by another planet in its orbit of the Sun.
D)It held that the planets moved along small circles that moved on larger circles around Earth, and that the combined motion sometimes resulted in backward motion. |
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4)Which of the following is not one of, nor a direct consequence of, Kepler's Laws? 4) _______
A)The orbit of each planet about the Sun is an ellipse with the Sun at one focus.
B)More distant planets orbit the Sun at slower speeds.
C)A planet travels faster when it is nearer to the Sun and slower when it is farther from the Sun.
D)The force of attraction between any two objects decreases with the square of the distance between their centers.
E)As a planet moves around its orbit, it sweeps out equal areas in equal times. |
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5)Only one of the statements below uses the term theory in its correct scientific sense. Which one? 5) _______
A)Evolution is only a theory, so there's no reason to think it really happened.
B)I wrote a theory that is 152 pages long.
C)I have a new theory about the cause of earthquakes, and I plan to start testing it soon.
D)Einstein's theory of relativity has been tested and verified thousands of times. |
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6)Which of the following has your "cosmic address" in the correct order? 6) _______
A)you, Earth, Local Group, Local Supercluster, solar system, Milky Way Galaxy, universe
B)you, Earth, solar system, Local Group, Local Supercluster, Milky Way Galaxy, universe
C)you, Earth, solar system, Local Group, Milky Way Galaxy, Local Supercluster, universe
D)you, Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe
E)you, Earth, Milky Way Galaxy, solar system, Local Group, Local Supercluster, universe |
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7)The great contribution of Nicholas Copernicus was to 7) _______
A)create a detailed model of our solar system with the Sun rather than Earth at the center.
B)prove that Earth is not the center of the universe.
C)discover the law of gravity.
D)discover the laws of planetary motion. |
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8)Which of the following is not consistent with the major hallmarks of science? 8) _______
A)Scientific explanations should be based solely on natural causes.
B)Science progresses through the creation and testing of models that explain observation as simply as possible.
C)Science consists of proven theories that are understood to be true explanations of reality.
D)A scientific model must make testable predictions. |
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9)Which of the following best describes the Milky Way Galaxy? 9) _______
A)a spiral galaxy with a disk about 100,000 light-years in diameter and containing about 100,000 stars
B)a spiral galaxy with a disk about 100,000 light-years in diameter and containing between 100 billion and 1 trillion stars
C)a spherically shaped collection of about 1 million stars that is about 100 light-years in diameter
D)a spiral galaxy with a disk about a billion kilometers in diameter and containing between 100 million and 1 billion stars
E)a spherically shaped collection of stars including our solar system and about a dozen other solar systems, stretching about 4 light-years in diameter |
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10)During the period each year when we see Mars undergoing apparent retrograde motion in our sky, what is really going on in space? 10) _______
A)Mars is moving around the Sun in the opposite direction from which Earth is moving around the Sun.
B)Earth and Mars are on opposite sides of the Sun.
C)Earth and Mars are getting closer together.
D)Earth is catching up with and passing by Mars in their respective orbits. |
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11)Which of the following statements about the celestial sphere is not true? 11) _______
A)When we look in the sky, the stars all appear to be located on the celestial sphere.
B)Earth is placed at the center of the celestial sphere.
C)The celestial sphere does not exist physically.
D)The "celestial sphere" is just another name for our universe. |
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13)How does Earth's varying distance from the Sun affect our seasons? 13) _______
A)It causes the seasons to be more extreme than they would be if Earth's distance from the Sun were always the same.
B)It doesn't—Earth's orbital distance plays no obvious role in the seasons.
C)It makes summer warmer in the Northern Hemisphere than in the Southern Hemisphere.
D)It is responsible for the fact that the seasons are opposite in the Northern and Southern hemispheres. |
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12)What do the structures of Stonehenge, the Templo Mayor, the Sun Dagger, and the Big Horn Medicine Wheel all have in common? 12) _______
A)They were all used by ancient peoples for astronomical observations.
B)They were all built on the orders of ancient kings.
C)They were all places used for religious sacrifice.
D)They all can be used as lunar calendars. |
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14)Based on observations of the universal expansion, the age of the universe is about 14) _______
A)14 million years. B) 14 trillion years.
C)14,000 years. D) 14 billion years. |
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15)You observe a full moon rising at sunset. What will you see 6 hours later? 15) _______
A)a first quarter moon
B)a waning gibbous moon
C)a third quarter moon
D)a full moon on or near your meridian |
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16)What is the ecliptic plane? 16) _______
A)the plane of Earth's orbit around the Sun
B)the plane of the Sun's equator
C)the plane of Earth's equator
D)the plane of the Milky Way Galaxy |
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17)Where is our solar system located within the Milky Way Galaxy? 17) _______
A)in the halo of the galaxy
B)roughly halfway between the center and the edge of the visible disk of the galaxy
C)very near the center of the galaxy
D)at the far edge of the galaxy's visible disk |
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18)If our year were twice as long (that is, if Earth took twice as many days to complete each orbit around the Sun), but Earth's rotation period and axis tilt were unchanged, then 18) _______
A)the cycle of precession would take 13,000 years instead of 26,000 years.
B)stars would take twice as long to rise and set.
C)the four seasons would each be twice as long as they are now.
D)Earth would not have seasons. |
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19)Which practical value did astronomy offer to ancient civilizations? 19) _______
A)It helped them find uses for ancient structures like Stonehenge.
B)It helped them keep track of time and seasons, and it was used by some cultures for navigation.
C)It allowed them to predict eclipses with great accuracy.
D)It helped them understand our cosmic origins. |
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20)Lunar eclipses can occur only during a 20) _______
A)first quarter moon.
B) new moon.
C)full moon.
D) third quarter moon. |
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21)Why do the patterns of the stars in our sky look the same from year to year? 21) _______
A)Although these stars move quite fast as they orbit around the Milky Way Galaxy, they all move together so they don't change their relative positions.
B)Although these stars move quite fast by human standards, they are so far away that it would take thousands of years for their motion to be noticeable to the eye.
C)Although these stars are moving, they move so slowly—typically about the speed of a snail—that their motion is not noticeable.
D)These stars are not moving. |
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22)How many arcseconds are in 1°? 22) _______
A)3,600 B) 100 C) 360 D) 60 E) 10,000 |
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23)Which of the following best describes how modern astronomers view astrology? 23) _______
A)Astrology is a synonym for astronomy.
B)Astrology was a great idea until it was disproved by the work of Copernicus, Tycho, Kepler, and Galileo.
C)Astrology played an important part in the development of astronomy in ancient times, but it is not a science by modern standards.
D)Astrology is new age mumbo-jumbo that was a waste of time when it was invented thousands of years ago and remains a waste of time today. |
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24)Suppose you are facing north, and you see the Big Dipper close to your northern horizon, with Polaris (and the Little Dipper) above it. Where will you see the Big Dipper in six hours?
A)still in the same place, below Polaris
B)to the right of Polaris; that is, 90° counterclockwise from its current position
C)directly above Polaris
D)to the left of Polaris; that is, 90° clockwise from its current position |
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25)Each part below describes how a few astronomical phenomena are related to time periods. Which list is correct? (Careful: some lists are partially correct.) 25) _______
A)Earth's rotation defines a day.
The Sun's rotation defines a week.
The Moon's rotation defines a month.
Earth's orbit defines a year.
B)Earth's rotation defines a day.
The cycle of the Moon's phases takes about a week.
Earth's orbit defines a year.
Earth's cycle of axis precession defines a month.
C)Earth's rotation defines a day.
The cycle of the Moon's phases takes about a month.
Earth's orbit defines a year.
Earth's cycle of axis precession takes 26,000 years.
D)Earth's rotation defines a day.
The saros cycle of eclipses defines a month.
Earth's orbit defines a year.
Earth's cycle of axis precession takes 26,000 years. |
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26)Approximately how fast are you moving with the rotation of Earth? 26) _______
A)13,000 km/hr
B)130 km/hr
C)1,300 km/hr
D)13 km/hr
E)not moving at all |
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27)About how many stars are visible to the naked eye on a clear, dark night away from city lights? 27) _______
A)a few dozen B) several million
C)a couple thousand D) a few hundred billion |
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28)When we look at an object that is 1,000 light-years away, we see it 28) _______
A)looking just the same as our ancestors would have seen it 1,000 years ago.
B)as it was 1,000 light-years ago.
C)as it is right now, but it appears 1,000 times dimmer.
D)as it was 1,000 years ago. |
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29)Stars that are visible in the sky on any clear night of the year, at any time of the night, are called 29) _______
A)circumpolar.
B) celestial.
C)bright.
D) seasonal. |
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30)A typical galaxy is a 30) _______
A)large, glowing ball of gas powered by nuclear energy.
B)relatively small, icy object orbiting a star.
C)collection of a few hundred million to a trillion or more stars, bound together by gravity.
D)nearby object orbiting a planet.
E)system consisting of one or a few stars orbited by planets, moons, and smaller objects. |
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2)Which of the following is not evidence supporting the idea that our Moon formed as a result of a giant impact? 2) _______
A)The Moon's average density suggests it is made of rock much more like that of Earth's outer layers than that of Earth as a whole.
B)The Pacific Ocean appears to be a large crater—probably the one made by the giant impact.
C)Computer simulations show that the Moon could really have formed in this way.
D)The Moon has a much smaller proportion of easily vaporized materials than Earth. |
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3)At which lunar phase(s) are tides most pronounced (e.g., the highest high tides)? 3) _______
A)new moon only
B)both new and full moons
C)both first and third quarters
D)full moon only
E)third quarter moon only |
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4)Which of the following conditions lead you to see an absorption line spectrum from a cloud of gas in interstellar space? 4) _______
A)The cloud is cool and lies between you and a hot star.
B)The cloud is visible primarily because it reflects light from nearby stars.
C)The cloud is cool and very dense, so that you cannot see any objects that lie behind it.
D)The cloud is extremely hot. |
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5)How does the light-collecting area of an 8-meter telescope compare to that of a 2-meter telescope? 5) _______
A)The 8-meter telescope has 4 times the light-collecting area of the 2-meter telescope.
B)The 8-meter telescope has 16 times the light-collecting area of the 2-meter telescope.
C)The 8-meter telescope has 8 times the light-collecting area of the 2-meter telescope.
D)The answer cannot be determined from the information given in the question. |
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6)When a spinning ice skater pulls in his arms, he spins faster because 6) _______
A)there exists an unbalanced reaction force.
B)there is less friction with the air.
C)there is less friction with the ice.
D)his angular momentum must be conserved, so reducing his radius must increase his speed of rotation. |
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7)When considering light as made up of individual pieces, each characterized by a particular amount of energy, the pieces are called 7) _______
A)gamma rays.
B) wavicles.
C)photons.
D) frequencies. |
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8)Suppose you lived on the Moon. Which of the following would be true? 8) _______
A)Your mass would be less than your mass on Earth, but your weight would be the same as it is on Earth.
B)Both your weight and your mass would be the same as they are on Earth.
C)Both your weight and your mass would be less than they are on Earth.
D)Your weight would be less than your weight on Earth, but your mass would be the same as it is on Earth. |
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9)How do scientists determine the age of the solar system? 9) _______
A)radiometric dating of Moon rocks
B)radiometric dating of the oldest Earth rocks
C)radiometric dating of meteorites
D)from theoretical calculations based on how long it must have taken the planets to evolve to their present forms |
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10)Suppose you start with 1 kilogram of a radioactive substance that has a half-life of 10 years. Which of the following statements will be true after 20 years pass? 10) _______
A)You'll have 0.5 kilogram of the radioactive substance remaining.
B)You'll have 0.75 kilogram of the radioactive substance remaining.
C)You'll have 0.25 kilogram of the radioactive substance remaining.
D)All the material will have completely decayed. |
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11)Which of the following best describes the fundamental difference between two different chemical elements (such as oxygen and carbon)? 11) _______
A)They have different atomic mass numbers.
B)They have different names.
C)They have different numbers of electrons.
D)They have different numbers of protons in their nucleus. |
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12)In what way is Venus most similar to Earth? 12) _______
A)both planets are nearly the same size.
B)both planets have warm days and cool nights.
C)both planets have very similar atmospheres.
D)both planets have similar surface geology. |
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13)Which of the following represents a case in which you are not accelerating? 13) _______
A)going from 0 to 60 miles per hour in 10 seconds
B)slamming on the brakes to come to a stop at a stop sign
C)driving in a straight line at 60 miles per hour
D)driving 60 miles per hour around a curve |
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14)Which of the following is not a major difference between the terrestrial and jovian planets in our solar system? 14) _______
A)Terrestrial planets contain large quantities of ice and jovian planets do not.
B)Jovian planets have rings and terrestrial planets do not.
C)Terrestrial planets orbit much closer to the Sun than jovian planets.
D)Terrestrial planets are higher in average density than jovian planets. |
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15)The difference between speed and velocity is that 15) _______
A)velocity is calculated using a physics equation.
B)they are expressed in different units.
C)velocity also includes a direction.
D)velocity is the same as acceleration whereas speed is different. |
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16)If the frequency of an electromagnetic wave is doubled then the energy of the photon is
A)unchanged
B)quadrupled
C)half as great
D)doubled
E)one fourth as great |
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17)If the force on a mass is doubled while the mass is kept constant then the acceleration is
A)unchanged
B)half as great
C)one fourth as great
D)quadrupled
E)doubled |
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18)According to our theory of solar system formation, which law best explains why the solar nebula spun faster as it shrank in size? 18) _______
A)the law of conservation of angular momentum
B)Einstein's law that E = mc2
C)the law of universal gravitation
D)the law of conservation of energy |
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19)Each of the following describes an "Atom 1" and an "Atom 2." In which case are the two atoms different isotopes of the same element? 19) _______
A)Atom 1: nucleus with 6 protons and 8 neutrons, surrounded by 6 electrons.
Atom 2: nucleus with 7 protons and 8 neutrons, surrounded by 7 electrons.
B)Atom 1: nucleus with 7 protons and 8 neutrons, surrounded by 7 electrons.
Atom 2: nucleus with 7 protons and 7 neutrons, surrounded by 7 electrons.
C)Atom 1: nucleus with 8 protons and 8 neutrons, surrounded by 8 electrons.
Atom 2: nucleus with 8 protons and 8 neutrons, surrounded by 7 electrons.
D)Atom 1: nucleus with 4 protons and 5 neutrons, surrounded by 4 electrons.
Atom 2: nucleus with 5 protons and 5 neutrons, surrounded by 4 electrons.
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20)Which of the following is not an advantage of the Hubble Space Telescope over ground-based telescopes? 20) _______
A)It never has to close because of cloudy skies.
B)Stars do not twinkle when observed from space.
C)It is closer to the stars.
D)It can observe infrared and ultraviolet light, as well as visible light. |
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21)Absolute zero is 21) _______
A)0° Kelvin.
B) 0° Celsius.
C)100° Celsius.
D) 0° Fahrenheit. |
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22)Why are astronauts weightless in the Space Station? 22) _______
A)because there is no gravity in space
B)because the Space Station is constantly in free-fall around Earth
C)because the Space Station is moving at constant velocity
D)because the Space Station is traveling so fast |
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23)Which of the following lists the planets of our solar system in the correct order from closest to farthest from the Sun? 23) _______
A)Earth, Mars, Mercury, Venus, Jupiter, Saturn, Uranus, Neptune, Pluto
B)Mercury, Venus, Mars, Earth, Saturn, Jupiter, Neptune, Uranus, Pluto
C)Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
D)Mercury, Earth, Venus, Mars, Jupiter, Saturn, Neptune, Uranus, Pluto |
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24)What is the difference between a bound orbit and an unbound orbit around the Sun? 24) _______
A)A bound orbit is an orbit allowed by the universal law of gravitation, and an unbound orbit is not.
B)An object on a bound orbit has a gravitational attraction to the Sun, while an object on an unbound orbit does not.
C)An object on a bound orbit follows the same path around the Sun over and over, while an object on an unbound orbit approaches the Sun just once and then never returns.
D)A bound orbit is circular, while an unbound orbit is elliptical. |
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25)According to our theory of solar system formation, what are asteroids and comets? 25) _______
A)chunks of rock or ice that condensed after the planets and moons finished forming.
B)leftover planetesimals that never accreted into planets.
C)chunks of rock or ice that were expelled from planets by volcanoes.
D)the shattered remains of collisions between planets. |
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26)How is Einstein's famous equation, E = mc2, important in understanding the Sun? 26) _______
A)It explains the fact that the Sun generates energy by losing some 4 million tons of mass each day.
B)It explains why the Sun's surface temperature is about 6,000°C.
C)It explains why the Sun has a magnetic field strong enough to influence the atmospheres of the planets.
D)It explains why the Sun is so massive. |
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27)Which of the following statements about X rays and radio waves is not true? 27) _______
A)X rays and radio waves are both forms of light, or electromagnetic radiation.
B)X rays have higher frequency than radio waves.
C)X rays travel through space faster than radio waves.
D)X rays have shorter wavelengths than radio waves. |
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28)The planets never travel in a straight line as they orbit the Sun. According to Newton's second law of motion, this must mean that 28) _______
A)the planets are always accelerating.
B)the planets will eventually fall into the Sun.
C)the planets have angular momentum.
D)a force is acting on the planets. |
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29)From laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 486.1 nanometers (nm). The spectrum of a particular star shows the same hydrogen line appearing at a wavelength of 486.0 nm. What can we conclude? 29) _______
A)The star is getting hotter.
B)The star is getting colder.
C)The star is moving away from us.
D)The star is moving toward us. |
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30)According to our basic scenario of solar system formation, why do the jovian planets have numerous large moons? 30) _______
A)The large moons of the jovian planets were originally formed in the inner solar system, and these moons migrated out to join up with the jovian planets.
B)The many moons of the jovian planets remain one of the unexplained mysteries of the formation of our solar system.
C)As the growing jovian planets captured gas from the solar nebula, the gas formed swirling disks around them, and moons formed from condensation accretion within these disks.
D)Because of their strong gravity, the jovian planets were able to capture numerous asteroids that happened to be passing nearby, and these became the major moons of the jovian planets. |
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1)Which of the following would not be an expected consequence of global warming? 1) _______
A)melting of polar ice and glaciers
B)warming up the entire Earth by the same amount
C)an increase in the number and intensity of hurricanes
D)an increase in the severity of winter blizzards |
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2)When we see a meteor shower, it means that 2) _______
A)Earth is crossing the orbit of a comet.
B)you should duck and run for cover to avoid being blasted on the head by a rock from space.
C)an Earth-approaching asteroid has recently come very close to our planet.
D)the solar wind is unusually strong. |
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3)When you see the bright flash of a meteor, what are you actually seeing? 3) _______
A)The flash that occurs when a speeding rock from space hits the ground
B)A star that has suddenly shot across the sky
C)The glow from a pea-size particle and the surrounding air as the particle burns up in our atmosphere
D)Emission of visible light from a particle that has not yet entered Earth's atmosphere |
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4)Which statement is not thought to be true of all comets? 4) _______
A)All comets are leftover planetesimals that originally condensed beyond the frost line in the solar nebula.
B)All comets are icy in composition.
C)Comets are always followed by long tails.
D)All comets orbit the Sun. |
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5)Which of the following is not a piece of evidence supporting the idea that Pluto is a large comet of the Kuiper belt? 5) _______
A)Pluto's composition appears to match that of other known Kuiper-belt comets.
B)Pluto grows a coma and a long tail when it is at the point in its orbit closest to the Sun.
C)Triton, which must once have orbited the Sun before being captured by Neptune, is larger than Pluto.
D)Pluto's orbit is very similar to the orbits of other known Kuiper-belt comets. |
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6)Which of the following general statements about Earth's atmosphere is not true? 6) _______
A)Without the relatively rare gas called ozone, Earth's surface would be bathed in dangerous ultraviolet light from the Sun.
B)Gas high in the atmosphere absorbs dangerous X rays from the Sun.
C)The nitrogen and oxygen in Earth's atmosphere keep the surface pleasantly warm.
D)The oxygen in our atmosphere was released by living organisms. |
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7)What was the Shoemaker-Levy 9 impact? 7) _______
A)the impact of a fragmented comet on Jupiter, carefully observed by astronomers when it occurred in 1994
B)the ninth impact witnessed by astronomers in modern times
C)the impact that created the Moon's largest crater
D)the impact thought to have wiped out the dinosaurs |
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8)Suppose you find a meteorite made almost entirely of metal. According to current theory, which of the following statements must be true? 8) _______
A)Your meteorite was blasted off the surface of Mars by an impact.
B)Your meteorite is a fragment of an object from the Kuiper belt.
C)Radiometric dating will show the age of your meteorite to be 4.6 billion years.
D)Your meteorite is a fragment from the core of a large asteroid that had undergone differentiation and then was shattered by a collision. |
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9)From center to surface, which of the following correctly lists the interior layers of a terrestrial world? 9) _______
A)mantle, crust, core
B) core, mantle, crust
C)mantle, core, crust
D) core, crust, lithosphere |
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10)Overall, Jupiter's composition is most like that of 10) _______
A)the Sun.
B) an asteroid.
C)a comet.
D) Earth. |
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Definition
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11)Why does Jupiter have three distinct layers of clouds? 11) _______
A)The three layers represent clouds made of gases that condense at different temperatures and therefore different altitudes.
B)The three layers reflect regions of Jupiter's atmosphere with different overall chemical compositions.
C)Clouds form randomly, so on average there are always three layers.
D)Jupiter has three different types of wind, each of which makes a different type of cloud. |
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12)Why isn't there a planet where the asteroid belt is located? 12) _______
A)There was too much rocky material to form a terrestrial planet, but not enough gaseous material to form a jovian planet.
B)There was not enough material in this part of the solar nebula to form a planet.
C)Gravitational tugs from Jupiter prevented material from collecting together to form a planet.
D)The temperature in this portion of the solar nebula was just right to prevent rock from sticking together. |
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13)According to current understanding, which of the following is required in order for a planet to have rings? 13) _______
A)The planet must be at least as massive as Saturn.
B)The planet must once have had a large moon that came too close to it, shattering the moon and creating the ring particles.
C)The planet must orbit its star at a distance greater than Mars orbits the Sun.
D)The planet must have many small moons that orbit relatively close to the planet in its equatorial plane. |
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14)All of the statements below are true. Which one gives the primary reason why the surface of Venus today is some 450°C hotter than the surface of Earth? 14) _______
A)Venus has a much stronger greenhouse effect than Earth.
B)Venus has a higher atmospheric pressure than Earth.
C)Venus has a much higher reflectivity than Earth.
D)Venus is only about 73 percent as far from the Sun as Earth. |
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15)Which of the following statements comparing the jovian interiors is not thought to be true? 15) _______
A)They all have cores that contain at least some rock and metal.
B)They all have the same exact set of internal layers, though these layers differ in size.
C)Deep inside them, they all have pressures far higher than that found on the bottom of the ocean on Earth.
D)They all have cores of roughly the same mass. |
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16)Why does Earth have so little carbon dioxide in its atmosphere compared to Venus? 16) _______
A)Chemical reactions turned Earth's carbon dioxide into nitrogen.
B)Earth once had a lot of carbon dioxide, but it was lost to space during the heavy bombardment early in our solar system's history.
C)Earth's volcanoes outgassed far less carbon dioxide than those on Venus.
D)Earth has just as much carbon dioxide as Venus, but most of it is locked up in carbonate rocks rather than being free in the atmosphere. |
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17)Why is the sky blue (on Earth)? 17) _______
A)because molecules scatter red light more effectively than blue light
B)because deep space is blue in color
C)because the Sun emits mostly blue light
D)No one knowsthis is one of the great mysteries of science.
E)because gas molecules in the atmosphere scatter blue light more effectively than red light |
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18)Which of the following best explains why so many of the jovian moons have been more geologically active in the past than have the Moon or Mercury? 18) _______
A)The jovian moons are considerably larger than the Moon and Mercury and therefore have retained much more internal heat.
B)The jovian moons probably have far more internal heat generated by radioactive decay than do the Moon or Mercury.
C)Jovian moons are made mostly of ice that can melt or deform at much lower temperatures than can the rock and metal that make up the Moon and Mercury.
D)Because of their greater distances from the Sun, the jovian moons receive much less heat from the Sun. |
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19)The asteroid belt is located 19) _______
A)between the orbits of Earth and Mars.
B)between the orbits of Mars and Jupiter.
C)beyond the orbit of Neptune.
D)between the orbits of Jupiter and Saturn. |
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20)Which of the following statements about the moons of the jovian planets is not true? 20) _______
A)Many of the moons are made largely of ices.
B)Some of the moons are big enough that we'd probably call them planets if they orbited the Sun.
C)The majority of the moons are large enough to be spherical in shape, while only a few have the more potato-like shapes of asteroids.
D)Some moons have an atmosphere. |
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21)Which of the following best describes how the greenhouse effect works? 21) _______
A)Greenhouse gases absorb infrared light coming from the Sun, and this absorbed sunlight heats the lower atmosphere and the surface.
B)A planet's surface absorbs visible sunlight and returns this absorbed energy to space as infrared light. Greenhouse gases slow the escape of this infrared radiation, which thereby heats the lower atmosphere.
C)Greenhouse gases absorb X rays and ultraviolet light from the Sun, and this absorbed radiation then heats the atmosphere and the surface.
D)The greenhouse effect is caused primarily by ozone, which absorbs ultraviolet light and thereby makes the atmosphere much hotter than it would be otherwise. |
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22)Why is Saturn almost as big as Jupiter, despite its smaller mass? 22) _______
A)Jupiter's greater mass compresses it more, thus increasing its density.
B)Saturn's rings make the planet look bigger.
C)Saturn has a larger proportion of hydrogen and helium than Jupiter, and is therefore less dense.
D)Saturn is further from the Sun, thus cooler, and therefore less compact.
E)Jupiter's strong magnetic field constrains its size. |
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23)Which statement is not true? 23) _______
A)Objects in the Oort cloud are made mostly of ice.
B)Objects in the asteroid belt and Kuiper belt orbit the Sun in nearly the same plane as the planets, but objects in the Oort cloud do not.
C)Objects in the asteroid belt are made mostly of rock and metal.
D)Objects in the Kuiper belt are made mostly of rock and metal. |
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24)Uranus and Neptune have methane clouds but Jupiter and Saturn do not. Which factor explains why? 24) _______
A)The stronger gravity on Jupiter and Saturn pulls methane downward so that it can't form clouds.
B)The rapid rotation of Jupiter and Saturn prevents methane clouds from forming.
C)Jupiter and Saturn do not contain any methane gas.
D)Temperatures on Jupiter and Saturn are too high for methane to condense. |
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25)The most volcanically active body in our solar system is 25) _______
A)Earth.
B) Europa.
C) Io.
D) Triton. |
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26)What do we mean when we say that the terrestrial worlds underwent differentiation? 26) _______
A)Their surfaces show a variety of different geological features resulting from different geological processes.
B)They lost interior heat to outer space.
C)At a time when their interiors were molten, denser materials sank toward their centers and lighter materials rose toward their surfaces.
D)The five terrestrial worlds are started similarly but ended up looking quite different. |
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27)What is the Great Red Spot? 27) _______
A)The Great Red Spot is a place where reddish particles from Io impact Jupiter's surface.
B)The Great Red Spot is a hurricane that comes and goes on Jupiter.
C)The Great Red Spot is a region on Jupiter where the temperature is so high that the gas glows with red visible light.
D)The Great Red Spot is a long-lived, high-pressure storm on Jupiter. |
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28)Which of the following most likely explains why Venus does not have a global magnetic field like Earth? 28) _______
A)It does not have a metallic core.
B)It has too thick of an atmosphere.
C)Unlike Earth, Venus does not have a liquid outer core.
D)Its rotation is too slow. |
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29)Which direction do a comet's dust and plasma tails point? 29) _______
A)perpendicular to the ecliptic plane
B)straight behind the comet in its orbit
C)always almost due north
D)generally away from the Sun |
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30)All the following statements about Mars are true. Which one might have led to a significant loss of atmospheric gas to space? 30) _______
A)Mars probably once had a much higher density of greenhouse gases in its atmosphere than it does today.
B)The axis tilt of Mars is thought to change significantly with time.
C)The rock on Mars is probably red because of chemical reactions with oxygen that had been released into the atmosphere through the outgassing of water molecules.
D)Mars lost any global magnetic field that it may once have had. |
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4)What is the solar wind? 4) _______
A)It is the strong winds that blow across the surface of the Sun, causing sunspots to move around randomly.
B)It is the name we give to the gas (or plasma) particles flowing outward from the surface of the Sun into the solar system.
C)It is the uppermost layer of the Sun, lying just above the corona.
D)It is the wind that causes huge arcs of gas to rise above the Sun's surface, sometimes staying aloft for weeks. |
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5)If Star A is close to us than Star B, then Star A's parallax angle is 5) _______
A)smaller than that of Star B.
B)fewer parsecs than that of Star B.
C)hotter than that of Star B.
D)larger than that of Star B. |
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6)Which of the following statements about spectral types of stars is not generally true? 6) _______
A)The spectral type of a star can be used to determine its surface temperature.
B)The spectral type of a star can be used to determine its distance.
C)The spectral type of a star can be used to determine its color.
D)The spectral type of a star can be determined by identifying lines in its spectrum. |
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7)What processes are involved in the sunspot cycle? 7) _______
A)the winding of magnetic field lines due to variations in the Sun's rotation
B)variations of the solar thermostat
C)gravitational contraction of the Sun
D)wave motions in the solar interior |
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8)The phase of matter in the Sun is 8) _______
A)solid.
B)plasma.
C)gas.
D)liquid.
E)a mixture of all of the above |
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9)Which event marks the beginning of a supernova? 9) _______
A)the beginning of neon burning in an extremely massive star
B)the sudden initiation of the CNO cycle
C)the onset of helium burning after a helium flash
D)the sudden collapse of an iron core into a compact ball of neutrons |
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10)The interstellar clouds called molecular clouds are 10) _______
A)clouds that contain little hydrogen and instead are made predominantly of complex molecules such as carbon dioxide and sulfur dioxide.
B)the hot clouds of gas expelled by dying stars.
C)another name for Herbig-Haro objects.
D)the cool clouds in which stars form. |
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11)All stars are born with the same basic composition, yet stars can look quite different from one another. Which two factors primarily determine the innate characteristics of a star? 11) _______
A)its apparent brightness and its luminosity
B)its mass and its stage of life
C)its apparent brightness and its distance
D)its mass and its surface temperature
E)its age and its location in the galaxy |
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15)Why can the fusion of carbon occur in intermediate- and high-mass stars but not in low-mass stars? 15) _______
A)It is because only high-mass stars do fusion by the CNO cycle.
B)It is because the cores of low-mass stars never get hot enough for carbon fusion.
C)It is because carbon fusion can occur only in the stars known as carbon stars.
D)It is because the cores of low-mass stars never contain significant amounts of carbon. |
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16)Suppose two stars are identical except that one is twice as far away from us as the other. Which statement is true? 16) _______
A)Both stars have the same apparent brightness, but the luminosity of the closer star is four times as great as that of the more distant star.
B)Both stars have the same luminosity, but the apparent brightness of the closer star is twice as great as that of the more distant star.
C)Both stars have the same luminosity, but the apparent brightness of the more distant star is four times as great as that of the closer star.
D)Both stars have the same luminosity, but the apparent brightness of the closer star is four times as great as that of the more distant star. |
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17)How is the lifetime of a star related to its mass? 17) _______
A)More massive stars live considerably longer lives than less massive stars.
B)More massive stars live considerably shorter lives than less massive stars.
C)More massive stars live slightly longer lives than less massive stars.
D)More massive stars live slightly shorter lives than less massive stars. |
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18)How do we know what goes on under the surface of the Sun? 18) _______
A)We have X-ray images from satellites of the interior of the Sun.
B)Astronomers create mathematical models that use the laws of physics, the Sun's observed composition and mass, and computers to predict internal conditions.
C)We have sent probes below the surface of the Sun.
D)By measuring Doppler shifts, we observe vibrations of the Sun's surface that are created deep within the Sun.
E)both B and D |
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19)Every second, the Sun converts 600 million tons of hydrogen into 596 million tons of helium. The remaining 4 million tons 19) _______
A)are converted to an amount of energy equal to 4 million tons times the speed of light squared.
B)are ejected into space by solar flares.
C)are ejected into space in a solar wind.
D)are reabsorbed as molecular hydrogen. |
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20)According to modern science, approximately how old is the Sun? 20) _______
A)400 million years
B) 25 million years
C)10,000 years
D) 4.6 billion years |
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21)Careful measurements reveal that a star maintains a steady apparent brightness at most times, except that at precise intervals of 73 hours the star becomes dimmer for about 2 hours. The most likely explanation is that 21) _______
A)the star is a Cepheid variable.
B)the star is a white dwarf.
C)the star is periodically ejecting gas into space, every 73 hours.
D)the star is a member of an eclipsing binary star system. |
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22)You discover a binary star system in which one star is a 15Msun main-sequence star and the other is a 10Msun giant. How do we believe that a star system such as this might have come to exist? 22) _______
A)Although both stars probably formed from the same clump of gas, the more massive one must have had its birth slowed so that it became a main-sequence star millions of years later than its less massive companion.
B)The giant must once have been the more massive star, but is now less massive because it transferred some of its mass to its companion.
C)The two stars probably were once separate, but became a binary when a close encounter allowed their mutual gravity to pull them together.
D)The two stars are simply evolving normally and independently, and one has become a giant before the other. |
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23)A spinning neutron star has been observed at the center of a 23) _______
A)supernova remnant. B) protostar.
C)red supergiant. D) planetary nebula. |
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24)Why does the Sun emit neutrinos? 24) _______
A)Convection releases neutrinos, which random walk through the radiation zone.
B)Fusion in the Sun's core creates neutrinos as a byproduct.
C)The Sun does not emit neutrinos.
D)Solar flares create neutrinos with magnetic fields. |
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25)The Sun's surface seethes and churns with a bubbling pattern. Why? 25) _______
A)The Sun's surface is boiling.
B)We are seeing hot gas rising and cool gas falling due to the convection that occurs beneath the surface.
C)The churning is an illusion created by varying radiation, as the gas on the Sun's surface is actually quite still.
D)The churning gas is being stirred up by the strong solar wind. |
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26)We do not know for certain whether the general trends we observe in stellar birth weights also apply to brown dwarfs. But if they do, then which of the following would be true? 26) _______
A)Brown dwarfs would be extremely rare.
B)Brown dwarfs would be responsible for most of the overall luminosity of our Milky Way Galaxy.
C)Most of the brown dwarfs in the Milky Way Galaxy would be quite young in age.
D)Brown dwarfs would outnumber all ordinary stars. |
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27)The overall result of the proton-proton chain is: 27) _______
A)6 H ⇒ 1 He + energy.
B)p + p ⇒ 2H + energy.
C)4 H ⇒ 1 He + energy.
D)Individual protons are joined into long chains of protons |
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28)When does a star become a main-sequence star? 28) _______
A)A star becomes a main-sequence star when a piece of a molecular cloud first begins to contract into a star.
B)A star becomes a main-sequence star when the rate of hydrogen fusion within the star's core becomes high enough to balance the rate at which the star radiates energy into space.
C)A star becomes a main-sequence star the instant that hydrogen fusion first begins in the star's core.
D)A star becomes a main-sequence star when it becomes luminous enough to emit thermal radiation. |
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29)What do we mean when we say that the Sun is in gravitational equilibrium? 29) _______
A)The Sun always has the same amount of mass, creating the same gravitational force.
B)The Sun maintains a steady temperature.
C)There is a balance within the Sun between the outward push of pressure and the inward pull of gravity.
D)The hydrogen gas in the Sun is balanced so that it never rises upward or falls downward. |
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30)The choices below each describe the appearance of an H-R diagram for a different star cluster. Which cluster is the youngest? 30) _______
A)The diagram shows main-sequence stars of spectral types G, K, and M, along with numerous giants and white dwarfs.
B)The diagram shows main-sequence stars of all the spectral types except O and B, along with a few giants and supergiants.
C)The diagram shows main-sequence stars of every spectral type except O, along with a few giants and supergiants.
D)The diagram shows no main-sequence stars at all, but it has numerous supergiants and white dwarfs. |
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1)What does Hubble's law tell us? 1) _______
A)The faster a spiral galaxy's rotation speed, the more luminous it is.
B)The more distant a galaxy, the faster it is moving away from us.
C)The longer the period of a Cepheid variable, the greater its luminosity.
D)For every force, there is an equal and opposite reaction force. |
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2)Which statement about pulsars is not thought to be true? 2) _______
A)All pulsars are neutron stars, but not all neutron stars are pulsars.
B)A pulsar must have a very strong magnetic field and rotate quite rapidly.
C)Pulsars can form only in close binary systems.
D)Pulsars are kept from collapsing by neutron degeneracy pressure. |
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3)How would you expect a star that formed recently in the disk of the galaxy to differ from one that formed early in the history of the disk? 3) _______
A)It should be higher in mass.
B)It should be much brighter.
C)It should orbit the galactic center at a much higher rate of speed.
D)It should have a higher fraction of elements heavier than hydrogen and helium. |
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4)Why are we unlikely to find Earth-like planets around halo stars in the Galaxy? 4) _______
A)Halo stars formed in a different way from disk stars.
B)Planets around stars are known to be extremely rare.
C)Halo stars do not have enough mass to hold onto planets.
D)Halo stars formed in an environment where there were few heavy elements to create rocky planets.
E)Any such planets would have been ejected long ago by galactic mergers. |
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5)What do we mean by the star-gas-star cycle? 5) _______
A)It is the set of nuclear reactions by which heavy elements are produced in the cores of massive stars.
B)It is the idea that stars in close binary systems can exchange gas with one another.
C)It is the continuous recycling of gas in the galactic disk between stars and the interstellar medium.
D)It is another name for what is sometimes called the galactic fountain, in which gas rises out of the disk and then falls back down. |
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6)What prevents a white dwarf from having a mass greater than the white dwarf limit (or Chandrasekhar limit)? 6) _______
A)White dwarfs are made only from stars that have masses less than the white dwarf limit.
B)White dwarfs get hotter with increasing mass, and above the white dwarf limit they would be so hot that even their electrons would melt.
C)Electron degeneracy pressure depends on the speeds of electrons, and as a white dwarf's mass approaches the white dwarf limit, its electron speeds are already approaching the speed of light.
D)The upper limit to a white dwarfs mass is something we have learned from observations, but no one knows why this limit exists. |
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7)Why are white-dwarf supernovae more useful for measuring cosmic distances than massive-star supernovae? 7) _______
A)We can see only white-dwarf supernovae in distant galaxies, not massive-star supernovae.
B)White-dwarf supernovae all have roughly the same true peak luminosity, while massive-star supernovae come in a wide range of peak luminosities.
C)White-dwarf supernovae follow a period-luminosity relation, while massive-star supernovae do not.
D)White-dwarf supernovae are much more common than massive-star supernovae. |
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8)According to current understanding, what is a quasar? 8) _______
A)any object with an extremely large redshift is called a quasar
B)a very large galaxy thought to be formed by the merger of several smaller galaxies, typically found in the center of a galaxy cluster
C)a galaxy with an unusually high rate of star formation
D)an active galactic nucleus that is particularly bright |
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9)What is an ionization nebula? 9) _______
A)Other galaxies are sometimes called ionization nebulae.
B)It is a colorful cloud of gas that glows because it is heated by light from nearby hot stars.
C)It is a region of very hot, low-density gas surrounding a recent supernova.
D)It is a clump of gas that will soon give birth to a new star. |
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10)Collisions between galaxies typically unfold over a period of 10) _______
A)several days.
B) several months.
C)thousands of years.
D) hundreds of millions of years. |
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11)What two properties of a Cepheid variable are directly related to one another? 11) _______
A)the period between its peaks of brightness and its luminosity
B)its luminosity and its mass
C)the period between its peaks of brightness and its distance
D)its mass and its distance |
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12)All the following types of objects are found almost exclusively in the disk (rather than halo) of the Milky Way except: 12) _______
A)globular clusters.
B)high-mass, red supergiant stars.
C)X-ray binaries.
D)young stars. |
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13)Suppose you drop a clock toward a black hole. As you look at the clock from a high orbit, what will you notice? 13) _______
A)The clock will fall toward the black hole at a steady rate, so that you'll see it plunge through the event horizon within just a few minutes.
B)The clock will fall faster and faster, reaching the speed of light as it crosses the event horizon.
C)Time on the clock will run faster as it approaches the black hole, and light from the clock will be increasingly blueshifted.
D)Time on the clock will run slower as it approaches the black hole, and light from the clock will be increasingly redshifted. |
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14)The primary way that we observe the atomic hydrogen that makes up most of the interstellar gas in the Milky Way is with 14) _______
A)space-based ultraviolet telescopes.
B)radio telescopes observing at a wavelength of 21 centimeters.
C)X-ray telescopes.
D)ground-based visible-light telescopes. |
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15)What do we call the bright, sphere-shaped region of stars that lie within a few thousand light-years of the center of the Milky Way Galaxy? 15) _______
A)the galaxy's halo
B) the galaxy's bulge
C)a globular cluster
D) the galaxy's disk |
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16)Will our Sun ever undergo a white dwarf supernova explosion? Why or why not? 16) _______
A)No, because the Sun's core will never be hot enough to fuse carbon and other heavier elements into iron.
B)No, because it is not orbited by another star.
C)Yes, about a million years after it becomes a white dwarf.
D)Yes, right at the end of its double-shell burning stage of life. |
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17)A neutron star is 17) _______
A)the remains of a star that died by expelling its outer layers in a planetary nebula.
B)a star made mostly of elements with high atomic mass numbers, so that they have lots of neutrons.
C)the remains of a star that died in a massive-star supernova.
D)an object that will ultimately become a black hole. |
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18)One possible explanation for a galaxy's type invokes the angular momentum of the protogalactic cloud from which it formed. Suppose a galaxy forms from a protogalactic cloud with a lot of angular momentum. Assuming its type has not changed due to other interactions, we'd expect this galaxy to be 18) _______
A)a torn and incoherent galaxy.
B) a spiral galaxy.
C)an irregular galaxy.
D) an elliptical galaxy. |
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19)What is an accretion disk? 19) _______
A)a disk of hot gas swirling rapidly around a white dwarf, a neutron star, or a black hole in a binary system
B)a disk of material found around every white dwarf in the Milky Way Galaxy
C)a disk around a young star in which planets can form
D)any flattened disk, such as the disk of the Milky Way Galaxy |
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20)According to our modern understanding, what is a nova? 20) _______
A)the explosion of a massive star at the end of its life
B)the sudden formation of a new star in the sky
C)a rapidly spinning neutron star
D)an explosion occurring on the surface of a white dwarf in a close binary system |
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21)Where are most heavy elements made? 21) _______
A)in the Big Bang, when the universe first began
B)in the interstellar medium
C)in stars and supernovae
D)none of the above
E)all of the above |
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22)Which of the following features is not a feature of a central dominant galaxy? 22) _______
A)They're found in clusters of galaxies.
B)They are often spiral galaxies.
C)They are thought to form by the merger of several smaller galaxies.
D)They often have multiple galactic nuclei near their centers. |
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23)If a neutron star or a black hole is accreting material from its companion in a close binary, which of the following observatories would offer us the best chance for discovering this fact? 23) _______
A)the SOFIA airborne infrared observatory
B)Arecibo Radio Observatory
C)Chandra X-Ray Observatory
D)Hubble Space Telescope |
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24)A standard candle is 24) _______
A)another name for a main-sequence star.
B)a light source of known brightness.
C)another name for a barred-spiral galaxy.
D)a 7-cm wax candle. |
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25)What do we mean by a protogalactic cloud? 25) _______
A)It is the cloud-like halo that surrounds the disks of spiral galaxies.
B)It is a cloud of matter that contracts to become a galaxy.
C)It is a cloud of hydrogen gas that we detect by studying absorption lines in a quasar's spectrum.
D)It was a term used historically to refer to any galaxy. |
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26)The most basic difference between elliptical galaxies and spiral galaxies is that 26) _______
A)elliptical galaxies lack anything resembling the halo of a spiral galaxy.
B)elliptical galaxies lack anything resembling the disk of a spiral galaxy.
C)elliptical galaxies have a spheroidal component (of stars distributed spherically about the galactic center), and spiral galaxies do not.
D)elliptical galaxies are very old and spiral galaxies are very young. |
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27)If we could see our own galaxy from 2 million light-years away, it would appear 27) _______
A)to fill the sky with widely spaced stars.
B)like a single, dim star.
C)as a faintly glowing band of light stretching all the way around the sky.
D)to be a flattened disk with a central bulge and spiral arms. |
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28)The Voyager spacecraft has a "postcard" designed to be understandable to any aliens that might someday encounter it. On the "postcard," scientists pinpointed the location of Earth by triangulating it between pulsars. Why did the scientists choose pulsars rather than some other type of star? 28) _______
A)Several pulsars are located within a dozen light-years of our solar system, making them useful for finding our solar system.
B)Pulsars are easy to identify by their almost perfectly steady periods of pulsation.
C)We're pretty sure that aliens will have only radio telescopes and not optical telescopes, so they'll have a better chance of seeing pulsars than ordinary stars.
D)Pulsars are very bright and therefore easy to find. |
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29)Which of the following statements is not true of the object known as Sgr A* in the center of our Galaxy? 29) _______
A)Its accretion disk is so large that it shines brightly in visible light.
B)It is thought to harbor a black hole of more than 2 million solar masses.
C)It is a source of bright radio emission.
D)It is a source of X-ray emission that we have observed with telescopes in space. |
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30)The more massive a white dwarf, the 30) _______
A)higher its luminosity.
B) higher its temperature.
C)smaller its radius.
D) larger its radius. |
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