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Second Semester Study Guide: Astronomy
The Moon
1. The distance between the Earth and the Moon
A. Remains constant as the Moon orbits about the Earth.
B. Varies as the Moon orbits about the Earth.
2. Which of the following is not a kind of geological feature found on the Moon?
A. Scarp
B. Crater
C. Maria
D. Rille
3. Basalt, a dense congealed lava rock rich in iron, is the primary material in the Moon's
A. Highlands.
B. Crust.
C. Maria.
D. Far side's regolith.
4. One result of bombardment of the Moon's surface is a layer of broken, pulverized, and powdered rock
called
A. Maria.
B. Regolith.
C. Basalt.
D. Lunar rays.
5. Based on a comparison between the amount of cratering seen in the highlands versus the maria, it is
possible to conclude that the main bombardment of the Moon occurred
A. Very recently.
B. About a million years ago.
C. About a billion years ago.
D. Shortly after the Moon formed a few billion years ago. E. All throughout the history of the Moon.
6. The primary reason the Moon lacks an atmosphere is because.
A. The Moon is made up of the wrong kinds of rocks to release atmospheric gases.
B. The Earth's gravity pulls away any atmosphere the Moon collects.
C. The Moon lacks sufficient gravity to retain an atmosphere.
D. There is no life on the Moon.
7. Which statement about the Moon's orbit is true?
A. The Moon is in synchronous rotation as it orbits the Earth.
B. The Moon is in a geosynchronous orbit around the Earth.
C. The Moon's orbit is aligned with the Earth's orbit.
D. The Moon rotates in the opposite direction than it orbits the Earth.
8. Which of the following theories for the origins of the Moon is general accepted by astronomers?
A. The Moon formed alongside the Earth (the twin theory).
B. The Moon is the result of a collision between the Earth and a Mars sized object in the early days of
the Solar System (the collision theory).
C. The Moon was originally a bulge on the Earth that was flung off by the rapidly spinning Earth (fission
theory).
D. The Moon formed somewhere else and was later captured by the Earth (capture theory).
9. If high tide is at noon, the next high tide will be at
A. Midnight.
B. 6 pm.
C. 6 am.
D. Noon tomorrow.
10. If the Moon were farther from the Earth, compared to now, the tides would be
A. About the same as now.
B. Neap tides would be shallower, and spring tides would be taller than now.
C. Less tall all the time.
D. Higher all the time.
11. How many times does the Moon rotate on its axis in one orbital period?
A. Only once.
B. Twice.
C. Several times.
D. The Moon does not rotate.
12. Why do we always see only one side of the Moon?
A. The Moon does not rotate.
B. The Moon is tidally locked with the Earth.
C. The far (opposite) side only faces the Earth during the daytime when the Sun's light outshines the
Moon.
D. From time to time we see all the sides of the Moon from the Earth.
13. From the observation that the same side of the Moon always faces the Earth, one can conclude that
A. The Moon does not rotate.
B. The Moon completes one rotation every day.
C. The Moon completes one rotation each time it completes an orbit about the Earth.
14. When our Earth becomes tidally locked with the Moon, which of the following statements will be
true?
A. The Moon will always be visible only from one side of the Earth.
B. There will be no eclipses.
C. The Moon will not go through phases.
D. An astronaut on the Moon would see only one side of the Earth.
E. Both A and D.
Survey of Solar Systems
1. Based on our understanding of our own solar system, which of the following would be most
surprising to observe in an extra-solar system of planets?
A. The planets nearest to the star have a lower density than the planets farther out.
B. Several planets show large tilts of their rotation axis compared to the plane of their orbits.
C. All the gas giants have moons.
D. Several planets have dense atmospheres containing carbon compounds.
2. Which of the following is not a method used by astronomers to detect and study exoplanets?
A. Rotational mapping.
B. Gravitational lensing.
D. Transit detection.
E. Direct imaging.
C. Doppler shift.
3. The Sun, the Earth, Jupiter, and Saturn's icy moons are all very different environments.
A. The result of each type of object forming from different interstellar clouds.
B. But their differences are only because of where each currently is in the solar system.
C. But all formed from the same basic group of chemicals.
D. But their differences are because each contains very different chemicals.
4. Which of the following observations does not inform astronomers about how the Solar System must
have formed.
A. All known ages for Solar System bodies are 4.6 billion years or younger.
B. The Solar System is flat in structure.
C. The farther out planets take longer to complete an orbit about the Sun.
D. The inner four planets are small and rocky, while the outer four planets are large and gaseous.
5. Given that Mercury, Mars, and some of the moons of the gas giants are covered with craters, why do
we not see lots of impacts happening today?
A. All the planetesimals have collided with planets already.
B. We would, but the impacts have always happened at a very slow rate and built up over billions of
years.
C. Most of the impacts happen on the far sides of these bodies.
D. The Sun's heat drove the remaining dust and gas out of the part of the solar system with planets, and
gravitational interactions ejected most of the larger debris.
6. Thinking about the formation of the solar system, what trend in composition would you expect to see
from the inside to the outside of the asteroid belt?
A. Rockier asteroids progressing towards ones with more hydrogen and carbon compounds.
B. Iron asteroids progressing more towards one with silicates.
C. Essentially the same composition all the way through.
D. Asteroids with hydrogen and carbon compounds, progressing towards asteroids made primarily of
ice.
E. Asteroids with hydrogen and carbon compounds, progressing towards asteroids made primarily of
iron and silicates.
7. How many stars are there in our Solar System?
A. One.
B. Eight.
C. Nine.
D. A few hundred.
E. About ten million.
8. Counting out from the Sun, which planet occupies the position after Jupiter?
A. Neptune
B. Mars
C. Venus
D. Earth
E. Saturn
9. When we see them in the night sky, which of the following objects are emitting their own light?
A. Mars
B. Venus
C. The Moon
D. The Sun
E. All of the above
10. How many planets are there in our Solar System?
A. 1
B. 4
C. 8
D. 9
11. The farthest planet of our Solar System is ________.
A. Mars
B. Venus
C. Jupiter
D. Neptune
12. Which planets have densities similar to that of the Earth's?
A. Mars and Mercury.
B. Jupiter and Saturn.
C. Uranus and Neptune.
13. In our Solar System, an object is called a planet if
A. It orbits the Sun.
B. It has the round shape.
C. It has cleared its neighborhood.
D. All of the above.
14. Pluto is classified as a dwarf planet because
A. It doesn't orbit the Sun.
B. It doesn't have the spherical shape.
C. It has not cleared its neighborhood.
D. All of the above.
15. A spherical region that surrounds the Solar System and extends up to about 100,000 AU from the
Sun is called the
A. Asteroid belt.
B. Kuiper belt. C. Oort cloud. D. Solar nebula
16. What is the name of the nebula from which our Solar System was formed?
A. Pseudo nebula
B. Solar nebula
C. Orion nebula
D. Crab nebula
17. Which property of the solar nebula was the most influential in giving the planets their
characteristics?
A. Mass
B. Pressure
C. Volume
D. Temperature
18. The process in which a gas cools and its molecules stick together to form liquid particles is called
A. Condensation.
B. Depression.
C. Evaporation.
D. Sublimation.
19. Which was the last part of the planet-forming process?
A. Formation of the atmosphere of the planets.
B. Formation of the planets' core.
C. Formation of the planetesimals.
D. Formation of the Sun.
20. Exoplanets are
A. Another name for dwarf planets.
B. The outer most planets in our Solar System.
C. Minor planets in the asteroid belt.
D. Planets around stars other than the Sun.
21. Why is it difficult to observe an exoplanet directly through a telescope?
A. Exoplanets produce very little of their own light.
B. Exoplanets are small compared to their parent star, so they reflect only a small portion of the star's
light.
C. Exoplanets tend to be far away from their parent stars, making it hard to get both the star and the
exoplanet in the telescope's field of view.
D. It is hard to see exoplanets against the blackness of space.
22. What is gravitational lensing?
A. The use of small telescopes to enhance the brightness of stars.
B. The focusing and brightening of starlight by the gravitational field of the foreground star, when there
is a perfect alignment with the observer.
C. The temporary disappearance of a star as an object passes in front of it.
D. The use of Earth's gravity to shape lenses during grinding.
23. Which of the following explains the rocky nature of the inner planets?
A. The lighter elements (hydrogen and helium) were sucked in by the Sun's gravity.
B. The Sun's gravity attracted the rocks to the inner part of the solar system.
C. Only the rocky material could condense at the higher temperatures of the inner part of the solar
nebula.
D. As the solar nebula was spinning, the light gasses were tossed to the outer parts of the disk.
24. According to the nebular hypothesis, which of the following sequences of events are chronologically
correct?
A. Solar nebula, interstellar cloud, collisions between planetesimals, accretion, planets.
B. Interstellar cloud, solar nebula, accretion, collisions between planetesimals, planets.
C. Interstellar cloud, accretion, solar nebula, collisions between planetesimals, planets.
D. Accretion, solar nebula, interstellar cloud, collisions between planets, planetesimals.
25. What conclusion can be drawn from the fact that some planets with solid surfaces and satellites
have impact craters?
A. Collisions between Solar System bodies and planetesimals were common at one time.
B. The young planets had softer surfaces.
C. Volcanoes were very active in the early stages of planet formation.
D. The Sun went through several explosions, ejecting material that scarred the planets and satellites.
26. Why was the recent discovery that planets more massive than Jupiter orbit nearby stars in small
orbits surprising?
A. Because according to the nebular hypothesis, massive planets should only form away from their star.
B. The density of these planets is very high.
C. According to the nebular hypothesis, planets cannot be larger than Jupiter.
D. The nebular hypothesis predicts that close in planets should have formed a second star.
27. Which of the following is the strongest evidence in support of the hypothesis that the solar system
was formed by the collapse of a gas and dust nebula?
A. Bode's law.
B. Images of other stars with gas and dust disks surrounding them.
C. The existence of large clouds.
D. The discovery of extra-solar planets.
28. Comets are _____ while asteroids are _____.
A. Icy; rocky
B. Large; small
C. Rocky; icy
29. Small planets do not have significant atmospheres because their _____ is weak.
A. Gravity
B. Magnetic field
C. Internal heating
30. Astronomers estimate that the age of the solar system is about ____ years.
A. 4.6 million
B. 4.6 billion
C. 4.6 trillion
D. 13.7 billions
31. Which of the following Solar System objects has a composition that most resembles the original solar
nebula?
A. The terrestrial planets.
E. Comets.
B. The jovian planets.
C. The dwarf planets.
D. The asteroids.
32. Compared to the _____ planets the ______ planets have _____.
A. Jovian; terrestrial; low density
B. Jovian; terrestrial; high escape velocity
C. Terrestrial; Jovian; small diameter
D. Terrestrial; Jovian; many satellites
33. Astronomers believe that the satellites of the Jovian planets were _____.
A. Formed by fission.
B. Formed by collisions with other objects.
C. Planetesimals orbiting the growing planet.
D. Formed elsewhere in the Solar System and were later captured by Jupiter's gravitational pull.
The Terrestrial Planets
1. What features are unique to Earth?
A. Canyons.
B. Volcanoes.
C. An atmosphere.
D. Precipitation.
E. None of these features are unique to Earth.
2. The red coloration seen on the Martian surface originates from
A. Past volcanic activity covering the surface of the planet with red lava.
B. When Mars' had flowing water, it also has red algae, which stained the surface rocks.
C. The atmosphere blocking out blue light, only allowing red light to reflect off of the surface.
D. The iron minerals in the surface rocks combining with oxygen in the atmosphere causing the surface
to rust.
3. Which planet is about half the size of the Earth?
A. Mercury
B. Venus
C. Earth
D. Mars
4. Which terrestrial planet is about one third the size of the Earth?
A. Mercury
B. Venus
C. Earth
D. Mars
5. List the terrestrial planets in increasing order of their size.
A. Mercury, Venus, Earth, Mars
B. Mercury, Mars, Venus, Earth
C. Earth, Mars, Venus, Mercury
D. Venus, Earth, Mars, Mercury
6. On which planet does plate tectonics take place?
A. Mercury
B. Venus
C. Earth
D. Mars
7. Which planet has the hottest surface temperature?
A. Mercury
B. Venus
C. Earth
D. Mars
8. The Coloris Basin found on Mercury was probably formed by what process?
A. Plate tectonics.
B. An impact from a planetesimal.
C. Volcanic activity.
D. Erosion from solar wind.
9. Which of the terrestrial planets does not have any craters?
A. Mercury
B. Venus
C. Earth
D. Mars
E. All of them have craters
10. Which planet has a greenhouse effect?
A. Mercury
B. Venus
C. Earth
D. Mars
E. Both B and C
11. List the terrestrial planets in decreasing order of their mass.
A. Mercury, Venus, Earth, Mars
B. Mercury, Mars, Venus, Earth
C. Earth, Venus, Mars, Mercury
D. Venus, Earth, Mars, Mercury
12. Mercury lacks an atmosphere because
A. Its close proximity to the Sun allows the Sun to gravitational pull gases directly off the surface of
Mercury.
B. Impacts from planetesimals caused its original atmosphere to evaporated away.
C. Its slow rotation allows atmospheric gases to escape the planet.
D. Its smaller size means it has gravitational attraction that is too weak to hold onto an atmosphere.
13. Which terrestrial planet has the most moons?
A. Mercury
B. Venus
C. Earth
D. Mars
14. Besides the Earth, which terrestrial planet also has seasons?
A. Mercury
B. Venus
C. Mars
D. Seasons are unique to the Earth
15. Which planet shows the largest variation of day and night temperatures?
A. Mercury
B. Venus
C. Earth
D. Mars
16. Which terrestrial planet is tilted upside down?
A. Mercury
B. Venus
C. Earth
D. Mars
17. Which of the terrestrial planets have the most similar atmospheric compositions?
A. Venus and Mars
B. Earth and Venus
C. Earth and Mercury
D. Mercury and Venus E. Earth and Mars
18. Which of the other terrestrial planets is closest in size to the Earth?
A. Mars
B. Venus
C. Mercury
19. Which of the following statements correctly compares the terrestrial planets?
A. Venus has the densest atmosphere and the highest average temperature.
B. Earth is the only planet that has active plate tectonics and surface water.
C. Mercury is the planet with the thinnest atmosphere and the smallest size.
D. All of the above.
20. The surface of Mercury resembles the Moon's surface in that they are both ______.
A. Eroded by wind
B. Newly resurfaced
C. Heavily cratered
D. Covered with volcanoes
21. ______ is the smallest of the terrestrial planets.
A. Venus
B. Earth
C. Pluto
D. Mars
E. Mercury
22. ______ is the largest of the terrestrial planets.
A. Jupiter
B. Earth
C. Venus
D. Mars
E. Mercury
23. The atmosphere of Venus consists mainly of ______.
A. Carbon dioxide
B. Sulfuric acid
C. Nitrogen and oxygen
D. Carbon monoxide
E. Hydrogen and helium
24. The clouds of Venus consist mainly of ______.
A. Carbon dioxide
B. Water vapor
C. Hydrogen and helium
D. Sulfuric acid
E. Carbon monoxide
25. The surface of Venus is dominated by _____.
A. Impact craters
B. Recent lava flows
C. Scarps
D. Large canyons
26. The Valles Marineris is ______ on the surface of Mars.
A. An old riverbed
B. A 4000 km canyon
C. A long scarp
27. The atmosphere of Mars consists mainly of ______.
A. Carbon dioxide
B. Carbon monoxide
C. Nitrogen
D. Oxygen
28. Mars' axial tilt and spin are most similar to _____.
A. The Earth's B. Mercury's
C. Venus'
29. Mercury's ________ and, therefore, the planet does not have seasons.
A. Axial tilt is zero
B. Orbit is too close to the Sun
C. Atmosphere is almost nonexistent
D. Orbit is a perfect circle
D. A large volcano
30. Venus‘ extremely high surface temperatures are due to
A. The composition of its atmosphere.
B. Volcanic activity.
C. Its relative close proximity to the Sun.
D. A recent impact that heated the planet.
31. Of all the terrestrial planets, ______ has the largest daily temperature variation.
A. Mercury
B. Venus
C. Earth
D. Mars
32. Of all the terrestrial planets, ______ has the highest surface barometric pressure.
A. Mercury
B. Venus
C. Earth
D. Mars
33. Which reason best explains why both Venus' and Mars' atmospheres are primarily carbon dioxide,
but the Earth's is much less than 1% carbon dioxide?
A. Earth's rocks had much less carbon and oxygen in them.
B. Venus and Mars, being smaller than Earth, can't retain the same mixture of gases as Earth.
C. Each planet has a significantly different surface temperature.
D. Plant life has existed on Earth for an extended amount of time.
34. Mercury's average density is about as high as the Earth's. This is most likely because
A. It contains a significantly higher fraction of iron than the Earth.
B. it is highly compressed by its own gravity.
C. It is composed of material blasted off the Earth in a collision.
D. Unlike the Earth, it does not have a (light) atmosphere that lowers its average density.
35. Evidence that there is a considerable amount of water frozen under the surface of Mars is provided
by all of the following except
A. Squishy-looking flow patterns around crater impact sites.
B. Features resembling channels cut by flowing water.
C. Periodic eruptions of geysers when subsurface ice is melted by volcanic activity.
D. Discovery by the Mars rovers of chemicals in surface rocks formed in the presence of large amounts
of water.
E. Satellite measurements of water in the polar caps.
36. Mercury's crust
A. Is molten because it is so close to the Sun.
B. May have been mostly lost after a collision with a large planetesimal.
C. Is much thicker than Earth's or Venus'.
D. Has an unusually high concentration of silicate rocks.
37. Mercury features long, steep cliffs in its crust called "scarps" which probably formed
A. After impacts from planetesimal or asteroid.
B. From floods of running water left to evaporate after comet impacts.
C. As plates of crust shifted as a result of massive earthquakes at a fault.
D. Like giant wrinkles as the crust cooled and shrank.
E. by erosion from high solar winds.
38. Maps of Venus have been made by
A. Landing spacecraft on the surface to take pictures.
satellites and the Earth.
B. Bouncing radio waves off the planet from
C. Optical telescopic observations from Earth when the clouds part.
D. Measuring seismic waves from earthquakes.
39. You would most likely find pancake-shaped lava domes on
A. Mercury
B. Venus
C. Earth
D. Mars
The Outer Planets
1. Which of the following lists the outer planets in order of increasing mass?
A. Jupiter, Saturn, Neptune, Uranus
B. Jupiter, Saturn, Uranus, Neptune
C. Saturn, Jupiter, Uranus, Neptune
D. Uranus, Neptune, Saturn, Jupiter
2. Together the Cassini spacecraft and its probe Huygens discovered which of the following features on
Titan?
A. Oceans.
B. Lakes near the polar regions.
D. An ice volcano.
E. B, C and D.
C. Dunes of ice crystals.
3. The surface structure of Saturn's largest satellite, Titan, is completely unknown because no spacecraft
so far could take pictures through Titan's thick clouds.
A. True, because no probe can pass through Titan's methane and ethane clouds.
B. True, because Titan's atmosphere blocks all wavelengths of electromagnetic radiation.
C. False. Recently in 2005, Cassini parachuted a probe into Titan's atmosphere and took the pictures of
its surface.
D. False, but all information related to Titan's surface comes from radar images taken by the Cassini
spacecraft.
4. What type of dunes exists on Titan?
A. Sand dunes.
B. Dust dunes.
D. We have not discovered any dunes on Titan.
C. Ice crystal dunes.
5. Of the outer planets, _________ has the smallest diameter.
A. Jupiter
B. Saturn
C. Uranus
D. Neptune
E. Pluto
6. Which of the out planets has rings?
A. Jupiter.
B. Saturn.
C. Uranus.
D. Neptune.
E. All of the outer planets have a ring system.
7. Which is the smallest of the outer planets?
A. Saturn
B. Jupiter
C. Uranus
D. Neptune
8. What observational evidence suggests that Uranus was struck by a large planetesimal early in its
formation?
A. Astronomers have identified a large impact crater on the surface of Uranus.
B. Uranus orbits the Sun in the opposite direction as the other planets.
C. Uranus' rotational axis is tipped over.
D. Uranus' moon Miranda shows a patchwork surface, suggesting a collision in its past.
9. Which is the largest planet?
A. Saturn
B. Jupiter
C. Uranus
D. Earth
E. Neptune
10. Which planet's rotation axis is closest to its orbital plane?
A. Saturn
B. Jupiter
C. Uranus
D. Earth
E. Venus
11. Which planet has the most extreme seasons?
A. Saturn
B. Jupiter
C. Uranus
D. Venus
E. Mercury
12. Which planet has the lowest density?
A. Saturn
B. Jupiter
C. Uranus
D. Earth
E. Neptune
13. Which planet has the largest satellite in the Solar System?
A. Saturn
B. Jupiter
C. Uranus
D. Mars
E. Mercury
14. Which satellite has lakes of liquid methane near its poles?
A. Ganymede
B. Io
C. Miranda
D. Triton
E. Titan
15. Although Saturn and Jupiter have similar compositions their outer appearances are different
because
A. Saturn's magnetic field is weaker than Jupiter's magnetic field.
B. Saturn's smaller size means it has a weaker gravitational field and thus less dramatic atmospheric
effects.
C. Saturn has more water molecules throughout its atmosphere giving it a uniform appearance.
D. Saturn's cooler temperatures allow for the formation of a hazy layer of ammonia clouds that
surrounds the planet.
16. The iron and rocky cores found inside Jupiter and Saturn are most closely in size to
A. An asteroid. B. The Moon.
C. The Earth.
D. The size of Jupiter and Saturn themselves.
17. How does the mass of Jupiter compare to the rest of the planets in the Solar System?
A. Jupiter's mass is greater than all the other planet masses combined.
B. Jupiter and Saturn have comparable masses.
C. Jupiter's mass is about equal to the sum of the terrestrial planet masses.
D. Jupiter's mass is about equal to the sum of Uranus and Neptune's masses.
18. What is the largest satellite (moon) in the Solar System?
A. Earth's moon
B. Jupiter's moon, Ganymede
C. Saturn's moon, Titan
D. Neptune's moon, Triton
19. Scientists believe a liquid water ocean might exist on the moon
A. Titan.
B. Europa.
C. Mimas.
D. Ganymede.
20. What causes the blue appearance of the planet Uranus?
A. Uranus' atmosphere contains methane that strongly absorbs red colors from the sunlight.
B. The planet is covered by an ocean of water.
C. The planet is very cold.
D. The composition of Uranus' atmosphere is the same as the Earth's atmosphere that makes the sky
blue.
21. Uranus completes an orbit around the Sun every 84 years and spins once every 17 hours,
approximately. Which of the following could be observed from the planet Uranus?
A. Season cycle of 84 years near the poles.
B. One sunrise every 17 hours on the equator.
C. Days lasting several years near the pole tipped toward the Sun.
D. Nights lasting several years near the pole tipped away from the Sun.
E. All of the above.
22. Compared to Uranus, Neptune has a smaller diameter and more mass. What can we conclude from
this comparison?
A. Neptune has higher average density than Uranus.
B. Uranus has higher average density than Neptune.
C. Uranus spins faster and therefore has a larger diameter.
D. The statement of the question is incorrect. Uranus is larger and has more mass than Neptune.
23. What prompted astronomers to search for Neptune?
A. Uranus was not following the precise orbit predicted by Newtonian physics.
B. An explosive impact on Neptune from a colliding planetesimal caught the attention of astronomers.
C. Bode's rule predicted a planet at the location of Neptune.
D. Nothing prompted astronomers to look for Neptune, it was found by accident.
24. The appearance of an aurora indicates that
A. The planet is being bombarded by small meteors.
B. There is a lot of lightning discharges in the planet's atmosphere.
C. The planet has a magnetic field.
D. There is intelligent life on the planet producing the aurora from below.
25. Which of the following accurately describes the properties of Saturn's rings?
A. The rings are a single, solid object.
B. The rings are very wide but very thin and composed of large planetesimals a few kilometers in size.
C. The rings are very wide but very thin and composed of small particles typically a few centimeters or
meters in size.
D. The rings are very wide but very thin veil of gas that surrounds the planet.
26. Which of the following is a common characteristic of the Jovian planets?
A. Mostly composed of hydrogen and helium.
B. Thick atmosphere.
C. Lack of solid surface.
D. Ring systems and satellites.
E. All of the above.
27. What chemical compound is responsible for Uranus and Neptune's color?
A. Complex organic compounds of sulfur and phosphorus.
C. Methane.
B. Ammonia.
D. Water.
28. Why do astronomers believe that the Jovian planets are composed mainly of hydrogen and helium?
A. Because hydrogen and helium are the main constituents of the solar system.
B. Because the Jovian planets are very large.
C. Because the Jovian planets have low densities.
D. The Voyager missions measured the chemical compositions of the interiors of the Jovian planets.
29. Why do astronomers believe that the Jovian planets must contain rocky material in their cores?
A. Because silicates and irons were part of the overall composition of the solar nebula.
B. Because the Jovian planets have large magnetic fields.
C. Because the Jovian planets have large gravity.
D. The statement of the question is incorrect. Astronomers believe that the Jovian planets consist
exclusively of hydrogen and helium.
30. Which of the following statements comparing Uranus and Neptune is correct?
A. Uranus has larger diameter and Neptune has more mass.
B. Uranus has larger diameter and more mass.
C. Neptune has larger diameter and smaller mass.
D. Neptune has larger diameter and more mass.
31. Of all the Jovian planets ______ shows signs of tectonic plate motion.
A. Jupiter
B. Saturn
C. Uranus
D. Neptune
E. None of the above
32. The colors of Jupiter's clouds suggest the presence of ______.
A. Organic molecules
B. Hydrogen and helium
C. Carbon dioxide
D. Red-shifted colors due to the fast motion
E. Iron oxides
33. The energy that stirs the circulation in Jupiter's atmosphere comes from _____.
A. The Sun
B. The planet's interior
C. The tidal force of the Galilean moons
D. The planet's magnetic field
34. The powerful _____ Jupiter is a result of the ______ and ______ in the interior of the planet.
A. Magnetic field of; Coriolis effect; heat generated
B. Wind on; rotation; excess hydrogen
C. Magnetic field; rapid rotation; heat generated
D. Wind on; Coriolis effect; heat generated
35. ________ is the largest of the Galilean moons.
A. Callisto
B. Europa
C. Ganymede
D. Io
36. The average density of the Galilean satellites of Jupiter _____ with increasing distance from the
planet.
A. Increases
B. Decreases
C. Does not change
37. The rings of Jupiter consist primarily of ______.
A. Small particles
B. Boulder-size rocks
C. Solid rings
D. Hydrogen and helium
38. The Great Red Spot on Jupiter is _____.
A. A large rising cloud of gas
B. A giant vortex that has persisted for over 300 years
C. A planetesimal impact site
D. A largo tornado sweeping the planet from north to south
39. ______ has the lowest density of all the planets in the solar system.
A. Pluto
B. Saturn
C. Mercury
D. Uranus
E. Jupiter
40. The rings of Saturn consist primarily of _____.
A. Hydrogen and helium
B. Silicate rocks
C. Water ice
41. The Roche limit refers to a _____.
A. Distance
B. Force
C. Speed
42. Compared the Galilean satellites, the larger satellites of Saturn have ____ average density.
A. Lower
B. Higher
C. About the same (as the Galilean satellites)
43. Astronomers believe that the interior of Saturn's satellites is mostly ____.
A. Ice
B. Rock
C. Hydrogen and helium
44. Spectral analysis of Titan's atmosphere indicates that it consists mainly of _____.
A. Carbon dioxide
B. Nitrogen
C. Hydrogen and helium
D. Oxygen
Small Bodies Orbiting the Sun
1. A comet that has a semi-major axis of 100 AU must have a period of about
A. 10 years.
B. 20 years.
C. 100 years.
D. 1000 years.
2. At its closest approach, a particular comet is about half an AU away from the Sun, and it's about 40
AU away at it's farthest point. The semi-major axis of the comet's orbit is about
A. 1/2 AU.
B. 20 AU.
C. 40 AU.
3. Astronomers believe chondrite meteorites are about 4.6 billion years old—formed when the solar
system formed—because
A. Their chemical composition suggests they are pieces broken off of Mars, which is believed to have
formed at that time.
B. There is no other reasonable time period in the solar system's history when any meteoroids could
have formed.
C. The chemicals they are made of were only common at the formation of the solar system.
D. Radioactive dating can be used to determine their age.
4. All of the asteroids in the asteroid belt together have
A. A tiny fraction of the Earth's mass. B. About the Earth's mass. C. About ten times the Earth's mass.
D. a mass somewhere between the mass of Mars and the mass of Jupiter.
5. Asteroids need to have enough material to have an average diameter of about _________ for gravity
to pull them into a spherical shape.
A. 100 km
B. 1000 km
C. 5000 km
D. 10000 km
6. Infrared observations are used to determine the mass of asteroids because
A. Asteroids reflect too little visible light to use optical telescopes for the measurements.
B. The infrared radiation is the glow of heat from the asteroid, and larger asteroids emit more infrared
light.
C. The Hubble Space Telescope only has infrared cameras.
D. Most asteroids are made of dark minerals which are more efficient at reflecting infrared light than
visible light.
7. How would you explain the average density of an asteroid being about 2 g/cm3, if the density of rock
is usually around 3 g/cm3?
A. The asteroid contains an unusually large quantity of helium.
B. The asteroid contains significant quantities of icy compounds.
C. The asteroid is made of fragments only loosely held together by gravity.
D. The asteroid is of the stony type, not the iron type.
8. Asteroids
A. Are small bodies, typically the size of a grain of sand or a boulder.
B. Can range is size from a few meters to many hundreds of kilometers.
C. Are larger objects, a few hundred kilometers in size, but not quite large enough to be classified as a
planet.
9. In the process of fluorescence, __________ is absorbed by an atom and the energy is emitted as
__________.
A. An ultraviolet photon; at least one visible light and one or more lower energy photons
B. A visible light and one or more lower energy photons; an ultraviolet photon
C. An ultraviolet and one or more lower energy photons; a visible light photon
D. A visible light photon; at least one ultraviolet and one or more lower energy photons
10. The tails streaming from a comet's coma are caused by
A. The comet leaving the material behind it as it travels forward.
B. Explosive forces from the hot nucleus ejecting the gas.
C. Radiation pressure and the particle wind from the Sun pushing them out.
D. The comet's magnetic field channeling and ejecting the particles of the tail.
11. Which of the following asteroids is now officially a dwarf planet?
A. Ceres
B. Itokawa
C. Ida
D. Eros
E. Methilde
12. Which probe smashed into Comet Tempel 1?
A. Stardust
B. Deep Impact
C. Hayabusa
D. NEAR
13. Fragments that do not completely burn in the atmosphere and eventually fall on the Earth are called
A. Meteoroids
B. Meteorites C. Meteors
D. Asteroids
14. A meteor shower occurs when the left over debris of a _______ intersects with our atmosphere to
produce the beautiful streaks of light.
A. Star
B. Asteroid belt C. Comet
D. Planet
15. Comets belong to the
A. Asteroid belt.
B. Kuiper belt. C. Oort cloud. D. Both A and B.
E. Both B and C.
16. To which compositional group do asteroids mainly belong?
A. Carbonaceous
B. Silicates
C. Metallic iron-nickel D. Icy water
E. A, B, and C are correct
17. Planet __________ creates the gaps in the asteroid belt called Kirkwood gaps.
A. Jupiter
B. Mars
C. Earth
D. Saturn
18. The gaps created by the planet Jupiter in the asteroid belt are called _______.
A. Asteroid gaps
B. Kepler gaps C. Kirkwood gaps
D. Jupiter gaps
19. Comets are rich in __________.
A. Water
B. Carbon monoxide (CO)
C. Carbon dioxide (CO2) D. All of the above
20. The short-period comets originate in _______ and the long-period comets originate in _______.
A. Kuiper belt; Oort cloud
B. Oort cloud; Kuiper belt
C. Kuiper belt; asteroid belt
D. Asteroid belt; Kuiper belt
21. The radiant is the common point from which __________ seem(s) to diverge.
A. Comets
B. Asteroids
C. A Meteor shower
D. Meteorites
22. Meteor showers are generally named
A. After the Greek Gods and Goddesses.
B. After the constellation from which they appear to diverge.
C. After the comet to which they belong. D. After the planet from which they seem to come to the
Earth.
23. What proves the existence of the Kuiper belt?
A. The existence of short period comets.
B. The fact that many comets orbit on the ecliptic.
C. The fact that comets are icy objects.
Hubble Space Telescope.
D. Objects of the Kuiper belt were detected by the
24. What is the evidence for the existence of the Oort cloud?
A. Objects of the Oort cloud were detected by the Hubble Space Telescope.
B. The fact that new comets continue to appear indicates that a distant reservoir of icy bodies must
exist.
C. The fact that many comets orbit on the ecliptic.
D. The fact that some comets have retrograde orbits.
25. The Leonid meteor shower occurs in mid November. Which of the following statements regarding
the Leonids is true?
A. The radiant of the meteor shower is in the constellation of Leo.
B. The shower occurs when the Earth crosses the path of an old comet.
C. The particles of the shower originate from the breakup of comet Leon R.
D. Both B and C.
E. Both A and B.
26. Halley's comet orbits the Sun approximately every 76 years. The planet Uranus orbits the Sun every
84 years at an average distance of 19 AU. Which of the statements regarding the orbit of Halley's comet
is correct?
A. According to Kepler's third law, the semi-major axis of Halley's comet is 18 AU.
B. Halley's comet remains within Uranus' orbit at all times.
C. The orbit of Halley's comet is very elliptical, therefore it can travel much farther from the Sun than
Uranus, but on the average is closer to the Sun than Uranus.
D. Both A and C.
E. None of the above.
27. What evidence supports the assumption that a large number of living species disappeared about 65
million years ago due to a catastrophic impact?
A. The existence of a thin iridium layer of comparable geological age.
B. The existence of a thin layer of soot of comparable geological age.
C. The Chicxulub crater.
D. All of the above.
28. Chondritic meteorites provide important clues because they are believed to
A. Contain grains from the first material that condensed out of the solar nebula.
B. Contain many rare metals.
C. be the only source of the necessary amino acids required for life.
D. be the source of all coal found on the Earth.
29. _____ travel(s) the farthest from the Sun.
A. Pluto
B. Comets
C. Asteroids
D. Charon
30. The Trojan asteroids orbit the Sun at an average distance of ____.
A. 60 ahead
B. 60 behind
C. 5.2 AU
D. 100,000,000 miles
31. The tail of a comet always points _____.
A. Forward
B. Backward
C. Away from the Sun
D. Toward the Sun
32. The typical size of a comet's nucleus is _____.
A. 10 m
B. 10 km
C. 100 km
D. 1000 km
E. 1 AU
33. Which of the following is not an outer planet?
A. Saturn
B. Jupiter
C. Uranus
D. Pluto E. Neptune
34. Which of the following are dwarf planets?
A. Uranus and Neptune
B. Neptune and Pluto
D. Eris and Uranus
E. Mercury and Eris
C. Pluto and Eris
35. Which Trans-Neptunian Object is largest in diameter?
A. Pluto
B. Sedna
C. Makemake
D. Eris
E. Orcus
36. The discovery of Charon was significant because it allowed astronomers to determine
A. The distance of Pluto.
B. The age of Pluto.
D. The radius of Pluto
E. Both C and D.
C. The mass of Pluto.
37. What is a useful result of the discovery that Charon occasionally eclipses Pluto?
A. It showed that eclipses occur in other parts of the solar system.
B. It allowed astronomers to determine the size of Pluto and Charon more accurately.
C. It allowed astronomers to image surface features of Pluto.
D. Both B and C.
38. Which of the following is a characteristic that Pluto shares with the Jovian planets?
A. It is mostly composed of hydrogen and helium.
B. It has a thick atmosphere.
C. It has a ring system.
E. None of the above.
D. All of the above.
The Sun, Our Star
1. Approximately how massive is the Sun as compared to the Earth?
A. 100 times
B. 300 times
C. 3000 times
D. 300,000 times
E. One million times
2. Which is more massive?
A. The Sun (a gaseous giant).
B. The Earth (a solid object).
3. Which is denser?
A. The Sun, which is about 300,000 times more massive than the Earth.
B. The Earth (a solid object).
4. If you could manage to stand on the Sun, you would weigh approximately ____ times more than your
weight on the Earth.
A. 10
B. 30
C. 100 D. 300,000
5. The sunlight we receive on the Earth originates from the Sun's
A. Radiative zone.
B. Photosphere. C. Chromosphere.
D. Corona.
6. The hottest part of the Sun is
A. The core.
B. The radiative zone.
C. The photosphere.
D. The Corona.
7. Approximately how long does energy take to travel from the core to the surface of the Sun?
A. A few seconds.
B. A few minutes.
D. 16 million years.
E. 10 billion years.
C. A thousand years.
8. The Sun's core is generating energy in the form of ________.
A. Gamma rays B. Ultraviolet
C. X-rays
D. Visible
E. Radio
9. Sunspots are dark because they are
A. Land masses like continents on the Earth.
B. Holes in the photosphere, allowing astronomers to view into the Sun's interior.
C. Shadows from clouds in the Sun's atmosphere.
D. Slightly cooler regions meaning they emit less light than the surrounding areas.
10. At which observatory listed below are scientists trying to capture neutrinos?
A. SOHO (Solar & Heliospheric Observatory).
B. Super Kamiokande, Japan.
C. GONG (Global Oscillations network group).
D. Hubble Space Telescope.
11. Which part of the Sun is covered with granules?
A. Corona
B. Chromosphere
C. Photosphere D. Core
12. Which part of the Sun is not in hydrostatic equilibrium?
A. Core
B. Radiation zone
C. Convection zone
D. Corona
13. The solar wind is created in the Sun's _______.
A. Core
B. Radiation zone
C. Convection zone
D. Corona
14. What is the name of a sudden, highly energetic, eruptive explosion on the surface of the Sun?
A. Sunspot
B. Granulation
C. Flare
D. Coronal hole
15. The diameter of the Sun is determined by measuring its ____ and _____.
A. Volume; density
B. Distance; volume
C. Distance; angular size
16. The surface temperature of the Sun can be measured using ____.
A. Kepler's third law
B. The Doppler shift
C. Wien's law
17. The temperature at the Sun's core is about _____.
A. 15,000,000 K
B. 1,500,000 K
C. 150,000 K
D. 15,000 K
18. The Sun's composition by the % of mass is 71% ____, 27% _____ and 2% _____.
A. Hydrogen; oxygen; helium
C. Hydrogen; helium; other elements
B. Helium; hydrogen; other elements
19. The energy in the Sun's core is produced by
A. Chemical reaction of hydrogen and helium.
B. Fusion of hydrogen to helium.
C. Radioactive decay.
D. Release of gravitational potential energy.
20. Light travels for about _____ to reach the Sun's surface from the Sun's core, and about ____ to reach
the Earth from the Sun's surface.
A. 16 million years; 8 minutes
B. 100 years; 8 minutes
C. 1 minute; 8 seconds
D. 100 years; 8 seconds
21. The Sun's atmosphere consists of the _____ and the _____.
A. Photosphere; chromosphere
B. Photosphere; corona
C. Chromosphere; corona
22. The temperature at the ____ of the Sun's chromosphere is higher than the temperature ____.
A. Base; at the top of the chromosphere
B. Top; at the base of the chromosphere
C. Top; of the Sun's corona
D. Base; of the Sun's corona
23. How is the composition of the Sun today different than when it formed 4.6 billion years ago?
A. There is no difference, the composition has not changed.
B. There is now more hydrogen and less helium.
C. There is now more helium and less hydrogen.
D. The amount of hydrogen and helium has not changed but the amount of heavier elements has
decreased.
24. ____ provides a way to measure the speed of seismic waves in the Sun.
A. Newton's 3rd law
B. Wien's law
C. The Doppler effect
D. Kepler's 3rd law
25. The Sun rotates _____ at its equator than at its poles.
A. Slower
B. The same
C. Faster
26. The _____ a period _______, that coincides with _______.
A. Sunspot cycle is; of 11 years; the Sun's rotation around its axis
B. Maunder Minimum is; of low sunspot activity; the "little ice age" in the late 17th century
C. Magnetic cycle is; of 22 years; a period of intense solar and earthquakes
D. Solar cycle is; of high sunspot activity; the cycle of the planetary alignments
27. A solar prominence is essentially
A. A cloud of hot gas lifting off the surface of the Sun.
B. An eruption of gas heated by the sudden recombination of opposite polarity parts of the Sun's
magnetic field.
C. A plasma confined to a magnetic tube sticking out of the surface of the Sun.
D. An aurora occurring in the Sun's atmosphere instead of the Earth's.
28. One way to probe the rate of nuclear reactions in the center of the Sun is by studying the _________
produced because _________.
A. Positrons; they annihilate into gamma rays of very specific energies.
B. Neutrinos; they pass out of the Sun without undergoing a random walk.
C. Heavy hydrogen; it has different spectral lines than normal hydrogen.
D. Wave motions; they can be measured at the Sun's surface.
29. Since nuclear fusion in the Sun creates energy from matter, why doesn't it violate the law of
conservation of energy?
A. Conservation of energy only applies to mechanical and electrical systems, not to nuclear physics.
B. The energy actually comes from the motion of the four separate hydrogen atoms, which move less
bound together as one helium atom.
C. Matter and energy are equivalent, as expressed by Einstein's equation E = mc2.
D. It does, but conservation of energy is only a law in Newtonian physics, which does not work under the
conditions at the center of the Sun.
30. If the Sun's rotation carries two sunspots around the side out of sight, you might see them again in
about
A. Twelve hours.
B. Two weeks. C. A month.
D. Six months.
31. Generally speaking, activity on the surface of the Sun is primarily driven by
A. Gravity.
B. Thermodynamics.
C. Electromagnetism.
D. Nuclear reactions.
32. The photosphere
A. Is the part of the Sun where nuclear fusion is occurring.
B. Is the layer of the Sun where it transitions from being opaque to transparent.
C. Is the hottest part of the Sun.
D. Is the densest part of the Sun.
33. From the center out, the correct order of the parts of the Sun is
A. Core, convection zone, radiative zone, photosphere, chromosphere, corona.
B. Radiative zone, core, chromosphere, convection zone, photosphere, corona.
C. Core, convection zone, photosphere, chromosphere, corona, radiative zone.
D. Core, radiative zone, convection zone, photosphere, chromosphere, corona.
34. The Zeeman effect, in which energy levels of electrons are shifted and produce a corresponding split
in spectral lines observed, is used to measure _________ at the Sun's surface.
A. Magnetic field strength
B. The intensity of gamma rays
C. Gravitational field strength
D. The velocity and oscillations of gas
35. The solar cycle is a result of the
A. Nuclear fusion at the core of the Sun.
B. Loss of energy in the Sun's magnetic field through flares, sunspots, and prominences.
C. Differential rotation of the Sun.
D. Motion in the convection zone cycling material into the Sun's core.
36. In the Sun, nuclear fusion occurs
A. In the core and the radiative zone.
B. Only in the core.
C. Throughout the entire star.
37. Although the Sun's core has a density much greater than rock it is considered a gaseous object
because
A. The Sun's high internal temperatures prevent the atoms from bonding together to form a liquid or a
solid.
B. A large fraction of the Sun's interior is made of electromagnetic radiation (light).
C. It is composed mostly of hydrogen.
D. The Sun formed from the solar nebula which itself was a large gas and dust cloud.
38. Astronomers know what the solar interior is like by
A. observing the interior directly. By using the appropriate filters it is possible to reduce the bright glow
of the Sun and to peer directly at the Sun's interior.
B. constructing a miniature Sun in the laboratory and extrapolating the results to the real Sun.
C. using locally tested physics combined with observations to build a mathematical model of what the
Sun should be like in its interior.
D. sending probes directly into the Sun and sending back the information.
Measuring the Properties of Stars
1. What is parallax?
A. The distance to an object, measured in parsecs.
B. The difference between the apparent and absolute magnitude.
C. The apparent shift in position of an object caused by a change in the observer's position.
D. The shift in angular position of an object as the object actually moves in space.
2. Parallax measurements of the distances to the nearest stars use _____ as a baseline.
A. Earth's orbit
B. Earth's diameter
C. Earth-Moon distance
D. About the length of a football field
3. The relative brightness of the stars as we see them in our sky is represented by their
A. Absolute magnitudes.
B. Apparent magnitude.
C. Surface temperature.
D. Luminosity.
4. Star A and Star B have same temperatures, but Star A is more luminous than Star B. Based on this
information, which of the following must be the case?
A. Star A is smaller than Star B.
B. Star A is larger than Star B.
C. Star A and Star B have same size.
D. Star A is more massive than Star B.
5. Luminosity (absolute brightness) of a star depends on its ___________.
A. Temperature
B. Radius
D. Both A and B
E. Both A and C
C. Distance from us
6. Star A and Star B have the same size, but Star A is more luminous than Star B. Based on this
information, which of the following must be the case?
A. Star A is cooler than Star B.
B. Star A is hotter than Star B.
C. Star A and Star B have same temperature.
D. Star A is more massive than Star B.
7. Which of the following stars has the hottest stellar surface temperature?
A. M6 B. A0
C. G5
D. B2
E. K9
8. Which of the following stars is reddish in color?
A. F6
B. A0
C. G5
D. B2
E. K9
9. If it were possible to move a star closer to the Earth then its apparent magnitude number would
______ while its absolute magnitude number would _______.
A. Decrease; increase
B. Decrease; stay the same C. Increase; decrease D. Increase; stay the same
10. In the above HR diagram sketch, which star is a white dwarf? A. A B. B
C. C
17. A star has a parallax angle of 0.2 arcseconds, which means it is at a distance of
A. 2 parsecs.
B. 2 light years. C. 5 parsecs.
D. 5 light years.
D. D
E. E
18. 80% of ________ type stars have orbiting companions.
A. O and B
B. A and F
C. F and G
D. K and M
19. In which binary system can we observe both the stars separately and follow their orbits around each
other?
A. Visual binary system.
B. Spectroscopic binary system.
C. Eclipsing binary system.
20. The H-R diagram is a diagram plotting the stars according to their
A. Apparent brightness and temperature.
B. Spectral type and temperature.
C. Brightness and luminosity class.
D. Luminosity and temperature.
E. Mass and diameter.
21. The star Aldebaran is a red giant, and is much more luminous than the Sun. What conclusions can be
drawn from this fact?
A. Aldebaran is hotter and much more massive than the Sun.
B. Aldebaran is cooler than the Sun, but has larger diameter than the Sun.
C. In the HR diagram, Aldebaran is above and to the left of the Sun.
D. Aldebaran is a binary star.
E. None of the above.
22. Which of the following is a main sequence star hotter than the Sun? (Note: the Sun is a G2V star)
A. B2II
B. G2II
C. G2III
D. G1V
E. O2II
23. The star Aldebaran is cooler and much more luminous than the Sun. Where do you expect to find
Aldebaran in the H-R diagram?
A. Top left
B. Top right
C. Center
D. Bottom right
E. Bottom left
24. Which of the following statements would explain the fact that larger molecules, such as amino acids,
do not produce spectral lines in the OBAFGKM classification?
A. Larger molecules require higher temperatures to show absorption lines.
B. The spectra of hydrogen and helium are sufficient to classify stars.
C. The spectra of larger molecules are too complicated.
D. Larger molecules break apart at the high temperatures of stellar atmospheres.
E. All of the above.
25. How can we explain the fact that hydrogen Balmer lines are essentially absent in the hot O type and
the cool M stars?
A. O type stars do not contain hydrogen. B. In cool stars hydrogen combines to form large molecules.
C. In O stars hydrogen is ionized and in M stars the electrons of hydrogen are in level 1, not level 2.
D. All of the above.
26. The spectrum of a star shows the 656 nm absorption line shifted to 654 nm. Which of the following
can we conclude about this star?
A. The star is approaching us with an approximate speed of 1,800 km/sec.
B. The star is receding with an approximate speed of 1,800 km/sec.
C. The star is approaching us with an approximate speed of 900 km/sec.
D. The star is receding with an approximate speed of 900 km/sec.
E. The star is spinning rapidly.
27. Binary star systems are very important because they allow
A. Measurement of star masses.
B. Measurement of the speed of stars.
C. More precise measurement of the distance of stars.
D. More precise measurement of the temperature of stars.
E. More precise measurement of the spectral type of stars.
28. What is the difference between spectroscopic and visual binaries?
A. Spectroscopic binaries have double spectral lines but do not move.
B. Visual binaries are pairs of stars in the same region in the sky but are not gravitationally interacting.
C. A visual binary does not show changes in the spectral lines.
D. In a visual binary we can see two distinct stars; in spectroscopic binaries, the images of the two stars
can not be resolved.
29. A visual binary star system has rotation period P = 10 years. The semi-major axis of the orbit of one
of the stars is 5 AU. What is the combined mass of the binary star system?
A. 0.4 solar masses.
B. 4 solar masses.
D. 40 solar masses.
E. 200 solar masses.
C. 8 solar masses.
30. The study of eclipsing binary stars is very important because it allows astronomers to determine
A. The distance between two stars. B. The speed of stars from the Doppler shift of their spectral lines.
C. The diameters of stars.
D. The luminosity of each star.
E. The brightness of each star.
31. Stars on the main sequence have different luminosities because
A. They have different chemical compositions.
B. They have different ages.
C. They are at different distances from the Sun.
D. They have different masses.
E. They have different apparent magnitudes.
32. If a main sequence, giant, and a supergiant all have the same spectral class, what characteristic is
known to make these stars different?
A. Luminosity. B. Distance.
C. Surface temperature.
E. It shows that the more massive stars are cooler.
D. Color.
33. Which of the following is not true for a pulsating star?
A. The surface temperature of a pulsating star changes periodically.
B. The outer layers of a pulsating star expand and contract periodically.
C. The luminosity changes periodically.
D. They are usually members of an eclipsing binary star system.
E. They show periodic shifts in their spectral lines.
34. What can we conclude about a star because its luminosity varies in an irregular pattern?
A. The star is very young.
B. The star is very old. C. The star is rotating. D. A or B.
35. If a star has an apparent magnitude of 8 and an absolute magnitude of 6 it is
A. Much closer than 10 parsecs away.
B. Slightly closer than 10 parsecs away.
C. Exactly 10 parsecs away.
D. Slightly farther than 10 parsecs away.
E. Much farther than 10 parsecs away.
36. _____ can be used to measure the _____ of nearby stars.
A. Parallax measurements; radius
B. The method of standard candles; brightness
C. Interferometry; radius
37. The parallax of a star is ____ usually measured in ____.
A. A distance; arcseconds
D. A distance; AUs
B. An angle; arcseconds
C. An angle; parsecs
38. If the distance between the Earth and a star is measured using parallax measurements, how far
apart in time should the two measurements be made to make the parallax measurement as accurate as
possible?
A. Instantaneously
B. A day
C. Six months
D. A year
39. If Star A has a parallax angle of 3 arc seconds while Star B has a parallax angle of 9 arc seconds then
we know that
A. Star A is three times farther away.
B. Star A is nine times farther away.
C. Star B is three times farther away.
D. Star B is nine times farther away.
40. The amount of energy emitted by a star each second is the ____ and is measured in ____.
A. Apparent brightness; degrees K
B. Temperature; degrees K
C. Apparent brightness; Watts
D. Luminosity; Watts
41. A light source at a distance of 1 meter that emits 50 Watts of visible radiation has the same ____ as a
source emitting 200 Watts and is located ____.
A. Luminosity; 2 meters away
B. Luminosity; 4 meters away
C. Apparent brightness; 2 meters away
D. Apparent brightness; 4 meters away
42. The luminosity of a star is determined by the star's ___ and ____.
A. Brightness; temperature
B. Apparent brightness; surface temperature
C. Diameter; surface temperature
D. Distance; surface temperature
E. Diameter; distance
43. A star of apparent magnitude 6 appears ______ times brighter than a star of apparent magnitude 7.
A. 1
B. 2
C. 2.51
D. ½
E. 10
44. A star of apparent magnitude ____ appears 2.51 times brighter than a star of apparent magnitude 4.
A. 1
B. 1.49
C. 3
D. 6.51
E. 10
45. Analysis of stellar spectra shows that most stars consist of 71% ___, 27% ___ and a 2% mix of the
other elements.
A. Hydrogen; oxygen
B. Hydrogen; helium
C. Helium; hydrogen
D. Oxygen; nitrogen
46. The Balmer lines correspond to wavelengths in the ____ part of the spectrum of a ____ atom.
A. Ultraviolet; helium
B. Visible; hydrogen
C. Infrared; hydrogen
D. X-ray; helium
47. Star A star is located at the top left of the H-R diagram and has the same luminosity as Star B which
is located at the top right of the H-R diagram. How must these stars differ?
A. Star A is hotter and bigger than Star B.
B. Star A is cooler and bigger than Star B.
C. Star A is hotter and smaller than Star B.
D. Star A is cooler and smaller than Star B.
48. An M type star 1000 times more luminous than the Sun will be located near the ___ part of the H-R
diagram.
A. Top left
B. Top right
C. Center
D. Bottom right
49. The hydrogen absorption lines are the strongest in ___ type stars.
A. A
B. B
C. O
D. G
50. Lines from molecules are strongest in ___ type stars.
A. A
B. F
C. M
D. K
E. O
E. Bottom left
51. In ___ stars most of the electrons in the hydrogen atom are above level 2 and in ___ stars most of
the electrons are below level 2, therefore the _____ are essentially absent in both types.
A. Type M; type O; Balmer lines
B. Type O; type M; Balmer lines
C. Type A; type M; emission lines
D. Type M; type A; absorption lines
E. Type O; type A; emission lines
52. ____ binary star systems are important because they allow astronomers to determine the mass and
the ____ of the stars in the system.
A. Eclipsing; temperature
B. Spectroscopic; diameter
D. Eclipsing; diameter
E. Visual; temperature
C. Spectroscopic; temperature
53. Analysis of ___ stars has shown that star masses are in the range of ___ to ____ solar masses.
A. Binary; 1; 10
B. Spinning; 1000; 0.1
D. Spinning; 1; 100
E. Binary; 30; 0.1
C. Binary; 100; 1
54. A main sequence star has 3 times the mass of the Sun. Using ____ we find that the star is ___ times
more luminous than the Sun.
A. The mass-luminosity relation; 9
B. The Stefan-Boltzmann law; 3
D. The mass-luminosity relation; 3
E. The inverse-square law; 9
55. White dwarfs have ____ spectral lines than red giants.
A. Narrower
B. Stronger
C. Weaker
D. Wider
C. Wien's law; 3
56. If Star A is twice as far as Star B, and they are identical in all other ways, then the brightness of Star A
would be
A. One-fourth the brightness of Star B.
B. One-half the brightness of Star B.
C. The same brightness as Star B.
D. Twice the brightness of Star B.
E. Four times the brightness of Star B.
-6) would have a surface
temperature of _________ and be an _________ star.
A. 2900 K; O
B. 2900 K; M
C. 29,000 K; O D. 29,000 K; M
58. How does Rigel, a bluish star, surface temperature compare to Betelgeuse, a reddish star.
A. Rigel's surface temperature is less than Betelgeuse's.
B. Rigel's surface temperature is greater than Betelgeuse's.
C. They have the same surface temperature because they are both members of the constellation Orion.
D. It is impossible to say without knowledge of the sizes of the stars.
59. If two stars are stacked vertically on an H-R diagram then they necessarily differ in their
A. Distance.
B. Luminosity class.
C. Spectral class.
D. Temperature.
Stellar Evolution
1. Brown dwarfs are
A. Large terrestrial planets.
B. Object massive enough to fuse deuterium but not massive enough to sustain hydrogen fusion.
C. Very low mass main sequence stars.
D. What is left over after a massive star ejects most of its material through a supernova.
2. The most important property that determines the evolution of a star is its
A. Temperature.
B. Composition.
C. Mass.
D. Location.
3. When do we say that a star is born?
A. When the interstellar cloud collapses.
B. When the interstellar matter achieves the Jeans instability.
C. When fusion of hydrogen atoms into helium atoms start.
D. When star leaves the main sequence.
4. The lifetime of a star is dependent on its ______.
A. Mass
B. Volume
C. Luminosity
D. Temperature
C. G and A
D. K and M
C. Visible.
D. X-ray.
5. What stars form the slowest?
A. O and B
B. A and F
6. Protostars shine brightest in
A. Radio.
B. Infrared.
7. The period-luminosity law of pulsating variable stars indicates that
A. The more slowly a star pulsates, the more luminous it is.
B. The faster a star pulsates, the more luminous it is.
C. Period of pulsation is independent of luminosity.
D. None of the above.
8. Which of the following elements in your body is formed in stars?
A. Carbon
B. Oxygen
C. Calcium
D. Iron E. All of the above
9. The Sun will leave the main sequence in about ______ years from now.
A. 5 million
B. 100 billion
C. 100 million D. 5 billion
10. If a star is in hydrostatic equilibrium
A. It is in a stable binary orbit.
B. It is generating energy at the same rate everywhere.
C. It is near the end of its life.
D. It must be losing mass.
E. Its radiation pressure outwards and gravitational forces inwards are in balance.
11. In which stage of a star's evolutionary cycle does it spend the most time?
A. The pre-main sequence.
B. The main sequence. C. The post-main sequence.
12. The process in which two or more lighter elements combine to form a single heavier element is
called
A. Nucleosynthesis.
B. Photodisintegration. C. Neutronization.
D. Fission.
13. When the outer envelope of a red giant is ejected, the remaining exposed core of a low mass star is
called a
A. Black hole.
B. Neutron star.
C. White dwarf.
D. Red super giant.
14. Which of the following statements about the "helium flash" is correct?
A. It does not occur in high-mass stars.
B. It does not occur in stars smaller than 0.5 solar masses.
C. It marks the end of the red giant stage for a star like the Sun.
D. It releases enough energy to change the degenerate gas in the core to normal gas.
E. All of the above.
15. After a star leaves the main sequence
A. It continues to fuse hydrogen into helium in its core.
B. It now fuses hydrogen into helium in a shell outside the core.
C. It no longer fuses hydrogen into helium anywhere inside the star.
16. What characteristic do all stars on the main sequence share?
A. They all have the same size.
B. They all have the same luminosity.
C. They all have the same temperature.
D. They are all fusing hydrogen into helium in their cores.
E. They will all go through a helium flash in the future.
17. What makes variable stars useful in determining star distances?
A. Their exact location in the H-R diagram is known.
B. They are brighter than other stars.
C. Their luminosity can be determined from their pulsation period.
D. They are easier to spot than ordinary stars.
18. Which of the following statements about planetary nebulas is correct?
A. They are shells of glowing gas and dust ejected by dying Sun-like stars.
B. They contain flakes of carbon and silicon material.
C. They expand at a typical rate of 20 kilometers per second.
D. Their shape can be very irregular.
E. All of the above.
19. Which of the following statements apply in the final moments of the life of high-mass stars?
A. Their outer layer is mainly hydrogen and helium.
B. Below the surface there is a series of nested shells each made of a lighter element than the one below
it.
C. They have iron cores.
D. The core temperature is about 2 billion degrees.
E. All of the above.
20. Which of the following statements about the evolution of high-mass stars is not correct?
A. High-mass stars evolve much faster than low-mass stars.
B. High-mass stars can fuse elements heavier than helium in their core.
C. High-mass stars stop fusing elements once they reach a carbon filled core.
D. High-mass stars do not have a helium flash.
E. The life of a high-mass stars ends with a supernova explosion.
21. How do most of the heavier elements up to iron form in the Universe?
A. In supernova explosions.
B. By nucleosynthesis in the cores of massive stars.
C. In the original interstellar clouds.
D. In the cores of protostars.
22. Where do most of the elements heavier than iron form?
A. In the interior of stars.
B. In the interior of high-mass stars.
C. In supernova explosions.
D. In the interstellar clouds.
23. How do astronomers test models of stellar evolution?
A. By comparing the paths in the H-R diagram predicted by models with the H-R diagrams of star
clusters.
B. By measuring the number of stars in a cluster and comparing with the number predicted by the
models.
C. By recording the properties of a star over an extended period of time.
D. By assuming that all the stars in our galaxy formed at the same time, and comparing with predictions
of the models.
24. Which of the following statements regarding the H-R diagrams of star clusters is not correct?
A. A very young cluster will have stars that lie in the right hand side and a little above the mainsequence.
B. A very old cluster will show a turn-off point and will have many red and yellow giant stars.
C. A very young cluster will not show a turn-off point.
D. A very old cluster will have many stars in the upper left corner of the H-R diagram.
E. A very young cluster will not have all its stars on the main sequence.
25. The Sun formed from the gravitational collapse of a cold ___.
A. Red giant
B. Planet
C. Planetary nebula
D. Interstellar cloud
26. For a star like the Sun, the gravitational collapse of the interstellar cloud lasted for about ____ and
stopped with the ignition of the fusion reaction.
A. 50-100 billion years B. 5-10 billion years
E. 1-10 million years
C. 1 billion years
D. 100 million years
27. ____ is the most significant force that determines the evolution of stars.
A. Temperature
B. Luminosity
C. Energy
D. Gravity
28. The main source of energy in main-sequence stars is ____.
A. Fusion of hydrogen to helium
B. Gravity
C. The triple alpha process
D. Chemical reaction between hydrogen and helium
29. A protostar becomes a main-sequence star when it _____.
A. Starts fusing helium
B. Starts fusing hydrogen to helium
C. Starts fusing heavier elements
D. starts glowing with infrared light
30. The typical temperature of an interstellar cloud that could collapse to a protostar is about ___.
A. 1500 K
B. 1000 K
C. 300 K
D. 10 K
31. Protostars are observable by radio telescopes but hard to detect in visible light because they have
_____ and are ____.
A. Low surface temperature; very distant
B. Small size; very hot
C. Low surface temperature; surrounded by dust
D. Small size; very distant
32. When a star moves off the main sequence and becomes a red giant it is brighter because
A. The star moves closer to the Earth.
B. The size of the star increases.
C. The surface temperature increases.
D. The star's mass increases.
33. A ____ is a region where jets of gas from young stars impact and heat the gas surrounding the young
star.
A. Planetary nebula
B. Bok globule C. Bipolar outflow
D. T Tauri star
34. In the H-R diagram a T Tauri star will be located ____.
A. Near the upper right corner
B. Near the upper left corner
C. Near the bottom left corner
D. Below the main sequence
E. On the right hand side and a little above the main sequence
35. Hydrostatic equilibrium is the balance between _____ of a star and _____.
A. The internal pressure; energy production
B. Hydrogen fusion; temperature
C. The size of the star; energy production
D. The internal pressure; gravity
36. A protostar is not _____.
A. Producing energy
B. Collapsing
C. In hydrostatic equilibrium
D. Heating up
37. The CNO cycle produces energy by fusing
A. Neon into Magnesium and Oxygen.
B. Hydrogen into helium.
C. Carbon and nitrogen into oxygen.
D. silicon into iron.
38. The triple alpha process produces energy by fusing ____ into ____.
A. Helium; carbon
B. Hydrogen; helium
D. Oxygen and carbon; carbon dioxide
C. Oxygen; carbon
E. Carbon and nitrogen; cyanogen
39. After the hydrogen in the star's core is depleted the core
A. shrinks and cools down.
B. shrinks and heats up.
C. expands and cools down.
D. Expands and heats up.
40. High-mass stars become ____ variables when they cross the instability strip, while low-mass stars
become ____ variables.
A. Cepheid; RR Lyrae
B. RR Lyrae; Cepheid
D. Cepheid; T Tauri
E. T Tauri; Cepheid
C. ZZ Ceti; RR Lyrae
41. The light curve of a large Cepheid variable would typically show pulsations in luminosity ____.
A. Every 6 minutes
B. Every 6 hours
C. Every 60 days
D. Every 6 months
E. Every 6 years
42. During a star's main sequence portion of its life it does not change size appreciably. This observation
indicates that
A. The Sun produces more energy than it radiates into space.
B. The Sun produces less energy than it radiates into space.
C. The Sun produces about the same amount of energy as it radiates into space.
43. The last fusion product possible in stars is _________ because _________.
A. Lead; fusing lead nuclei absorbs energy; it does not liberate it
B. Iron; fusing iron nuclei absorbs energy; it does not liberate it
C. Iron; no stars are hot enough in their cores to fuse iron nuclei
D. Carbon; no stars are hot enough in their cores to fuse carbon nuclei
44. Supernova remnants
A. Initially expand at thousands of km/s.
B. May contain up to 10 solar masses of material ejected from the star.
C. Are important for mixing material into the interstellar medium.
D. Both A and C.
E. A, B and C.
Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes
1. ___________ are hot, compact stars whose mass is comparable to the Sun's and size to the Earth's.
A. White dwarfs
B. Neutron stars
C. Pulsars
D. Black holes
2. Which of the following objects do you expect to find at the center of a planetary nebula?
A. Planet
B. Neutron star
C. White dwarf
D. Black hole
3. A __________ happens when a single high mass star explodes.
A. Nova
B. Type Ia supernova
D. Pulsar
E. None of the above
C. Type II supernova
4. A __________ happens when a white dwarf in a binary system accumulates more mass than
Chandrasekhar limit.
A. Nova
B. Type Ia supernova
C. Type II supernova
D. Pulsar
E. None of the above
5. This event recurs and happens when one of the companions in the binary system is a white dwarf.
A. Nova
B. Type I supernova
C. Type II supernova
D. Pulsar
E. None of the above
6. ___________ are hot, compact remnant stars whose mass is typically between one and several times
that of the Sun, but their size is only 10 km or less.
A. White dwarfs
B. Neutron stars
C. Pulsars
D. Black dwarfs
7. This recurring event happens in the case of a binary system in which one of the companions is a
neutron star.
A. Novae
B. Type I supernovae
C. Type II supernovae
D. X-ray bursts E. None of the above
8. Which of the following is a remnant of a dying star?
A. White dwarf
B. Neutron star
C. Black hole
D. All of the above
9. If stars rotate with periods of tens of days, why does a neutron star rotate several to thousands of
times a second?
A. When a neutron star collapses, the intensified magnetic field causes it to rotate much more quickly.
B. When a neutron star collapses, its rotation is kicked up by the ejected material from the supernova.
C. When a neutron star collapses, its rotation rate speeds up because of conservation of angular
momentum.
D. The collapsing neutron star becomes hot and the fast rotation is the result of thermal energy.
10. Two important properties of young pulsars are
A. Rapid rotation and no magnetic field.
B. No rotation and strong magnetic field.
C. Extremely rapid rotation and a weak magnetic field.
D. Extremely rapid rotation and a strong magnetic field.
E. No rotation and no magnetic field.
11. A method for identifying a black hole is to
A. Observe them directly through the space-based telescopes.
B. Look for voids (holes) in the star fields.
C. Look for its effect on nearby companions.
D. Search for radio waves from the accretion disk.
12. The escape velocity inside a black hole is
A. Zero.
B. Infinity.
C. Unknown.
D. Half the speed of light.
E. Greater than the speed of light.
13. What is the escape velocity at the event horizon of a black hole?
A. Speed of sound.
B. Supersonic speed.
C. Speed of light.
D. Half the speed of light.
14. Which of the following can actually escape a black hole?
A. Electrons.
B. Very high energy gamma-rays.
C. Visible light.
D. Very low energy radio waves.
E. None of the above.
15. The Chandrasekhar limit is the largest ______ a white dwarf can have.
A. Speed
B. Mass
C. Temperature
D. Wavelength
16. _______ are remnants of low mass stars.
A. Neutron stars
B. Pulsars
C. White dwarfs
D. Black holes
17. The mass of a black hole can be determined by _____.
A. Measuring its volume and density
B. the electromagnetic radiation it emits
C. how rapidly it is spinning
D. Applying the modified version of Kepler's 3rd law, if the black hole is in a binary system
18. The temperature of black holes is estimated to be ____.
A. Hotter than the Sun
B. Less than 1 millionth of a degree
C. Hotter than 1 million degrees
D. Hotter than a white dwarf
E. Black holes do not have temperature
19. Millisecond pulsars rotate about ______ times per second.
A. 10
B. 100
C. 1000
D. 1 million
20. In comparison to main sequence stars, which of the neutron star properties listed is not considered
extreme?
A. Magnetic field
B. Spin rate
C. Density
D. Mass
21. Black holes emit radiation in the form of ______ waves known as Hawking radiation.
A. gravitational
B. Electromagnetic
C. seismic
D. nuclear
22. The first pulsars were observed using _______ telescopes.
A. Optical
B. X-ray
C. Infrared
D. Radio
E. Gamma ray
23. The fast rotation of neutron stars is a consequence of _____.
A. Wien's law
B. The Doppler effect
C. Their high temperature
D. The law of conservation of angular momentum
24. Type Ia supernovas involve a ____.
A. White dwarf
B. Neutron star
C. Black hole
D. Planetary nebula
25. Compared to the Sun, white dwarfs have higher _____ and lower _____.
A. Masses; surface temperatures
B. Volumes; surface temperatures
C. Surface temperatures; luminosities
D. Luminosities; surface temperatures
26. White dwarfs have a surface composed of a thin layer of ____.
A. Hydrogen and oxygen
B. Hydrogen and helium
C. Carbon and oxygen
D. Carbon and helium
27. Astronomers use _____ to determine the magnetic field of white dwarfs.
A. The Doppler effect
B. Wien's law
C. Conservation of angular momentum
D. The Zeeman splitting of spectral lines
28. Why do white dwarfs have high temperatures?
A. Heat left over from their formation. B. Chemical reactions on their surfaces.
C. Nuclear fusion in their cores.
D. Frictional heating from motions inside the white dwarfs.
29. Gravitational waves
A. Are how pulsars pulse.
B. Carry material into black holes.
C. Are traveling distortions of space and time.
D. Do not carry energy.
30. If left in isolation a white dwarf will eventually
A. Cool off and become a black dwarf.
B. Explode as a Type Ia supernova.
C. Form a brown dwarf.
D. Become the seed for a new star.
31. An isolated black hole will
A. Eventually suck in all of the Universe.
B. Implode due to its own gravity.
C. Not change in any way.
D. Slowly evaporate away through the emission of Hawking radiation.