A) Polaris B) BetelgeuseC) Procyon B D) Sirius

1. Which star has a surface temperature most similar tothe surface temperature of Alpha Centauri?

A) hotter B) farther awayC) larger D) older

2. Giant stars have greater luminosity than our sunmainly because they are

Base your answers to questions 3 through 6 on the Characteristics of Stars graph below and on yourknowledge of Earth science.

3. Describe one characteristic of the star Spica that causes it to have a greater luminosity than Barnard'sStar.

4. The star Canopus has a surface temperature of 7400 K and a luminosity (relative to the Sun) of 1413.Use an X to plot the position of Canopus on the graph above, based on its surface temperature andluminosity.

5. Identify two stars from the Characteristics of Stars graph that are at the same life-cycle stage as theSun.

6. Describe how the relative surface temperature and the relative luminosity of Aldebaran would changeif it collapses and becomes a white dwarf like Procyon B.

A) reddish orange with low luminosity and highsurface temperature

B) reddish orange with high luminosity and lowsurface temperature

C) blue white with low luminosity and low surfacetemperature

D) blue white with high luminosity and high surfacetemperature

7. Which characteristics best describe the star Betelgeuse?

A) measure the size of a starB) measure the altitude of a starC) identify elements in the atmosphere of a starD) measure the diameter of a star

8. By using a spectroscope an astronomer can

Base your answers to questions 9 and 10 on the diagram below, which shows the change in the size ofa star such as our Sun as it evolves from a protostar to a white dwarf star.

A) protostar B) main sequence C) giant D) white dwarf

9. During which stage of development does the star have a cool surface temperature and the greatestluminosity?

A) radioactive decay B) nuclear fusionC) conduction D) convection

10. Which process produces the energy radiated by the star when it becomes a main sequence star?

A) blue B) whiteC) yellow D) red

11. Which star color indicates the hottest star surfacetemperature?

A) 300 ºC B) 3000 ºCC) 5000 ºC D) 10,000 ºC

12. Barnard's Star has a surface temperature of about

A) color and apparent brightnessB) color, apparent brightness and distanceC) apparent brightness and ageD) color and distance

13. In order to position a star on an H-R diagram youmust know at least the star's

Base your answers to questions 14 through 17 on the diagram below and on your knowledge of Earthscience. The diagram represents two possible sequences in the evolution of stars.

A) nuclear fusion B) thermal conductionC) convection currents D) radioactive decay

14. Which process generates the energy that is released by stars?

A) B)

C) D)

15. Which table includes data that are characteristic of the surface temperature and luminosity of somewhite dwarf stars?

A) mass B) color C) shape D) composition

16. Which property primarily determines whether a giant star or a supergiant star will form?

A) magnetism B) gravitational attractionC) expansion of matter D) cosmic background radiation

17. What causes clouds of dust and gas to form a protostar?

Base your answers to questions 18 and 19 on the graph below, which shows changes in the Sun’smagnetic activity and changes in the number of sunspots over a period of approximately 100 years.Sunspots are dark, cooler areas within the Sun’s photosphere that can be seen from Earth.

A) B)

C) D)

18. Which graph best represents the relationship between the number of sunspots and the amount ofmagnetic activity in the Sun?

A) randomly and unpredictablyB) precisely at the beginning of each decadeC) in a cyclic pattern, repeating approximately every 6 yearsD) in a cyclic pattern, repeating approximately every 11 years

19. The graph indicates that years having the greatest number of sunspots occur

A) Supergiant B) White dwarfC) Blue star D) Red Dwarfs

20. Which stars are the youngest?

A) Betelgeuse and Barnard's StarB) Procyon B and Proxima CentauriC) Polaris and the SunD) Alpha Centauri and Sirius

21. Which two stars are most similar in luminosity?

A) in the Sun by fusionB) when water condenses in Earth's atmosphereC) from the movement of crustal platesD) during nuclear decay

22. The reaction below represents an energy-producingprocess.

The reaction represents how energy is produced

23. Base your answer to the following question on the diagram below, which shows an inferred sequencein which our solar system formed from a giant interstellar cloud of gas and debris. Stage A shows thecollapse of the gas cloud, stage B shows its flattening, and stage C shows the sequence that led to theformation of planets.

A) when gravity caused the center of the cloud to contractB) when gravity caused heavy dust particles to split apartC) by outgassing from the spinning interstellar cloudD) by outgassing from Earth’s interior

From stage B to stage C, the young Sun was created

A) how fast the star is movingB) the strength of the light emanating from the starC) the distance from us to the starD) the amount and kind of obstacles between us

and the star

24. The apparent brightness of an object such as a stardoes not depend on

A) temperature B) diameterC) mass D) luminosity

25. Which of the following is the same for all stars alonga horizontal line on an H-R diagram?

A) contracting from a gas cloud (nebula)B) as a main sequence starC) moving away from the main sequence and becoming a giant starD) changing from a giant star to a white dwarf star

26. The Sun is inferred to spend the greatest amount of time in its life cycle

A) The star's temperature.B) The star's size.C) The star's distance.D) The star's shape.

27. Which factor does not affect a star's absolutemagnitude (Luminosity)?

A) Barnard's star B) ProcyonC) Alpha Centauri D) Rigel

28. Which star has the greatest luminosity?

A) brighter B) smallerC) cooler D) hotter

29. Compared to our sun, the star Polaris is

A) hydrogenB) heliumC) oil and various hydrocarbonsD) oxygen

30. The "fuel" of the sun is

A) carbon and hydrogenB) hydrogen and heliumC) helium and carbonD) carbon and heavy metals

31. What are the two most abundant elements in a mainsequence star?

Base your answers to questions 32 through 34 on the diagram below. The diagram represents theinferred stages in the formation of our solar system. Stage 1 shows a contracting gas cloud. Theremaining stages show the gas cloud flattening into a spinning disk as planets formed around our Sun.

A) larger diameters B) higher densitiesC) shorter periods of revolution D) longer periods of rotation

32. Compared to the terrestrial planets, the Jovian planets in stage 5 have

A) 1 billion years B) 5 billion yearsC) 20 billion years D) 100 billion years

33. Approximately how long ago did stage 4 end and stage 5 begin?

A) conduction B) radiationC) radioactive decay D) nuclear fusion

34. Which process was occurring during some of these stages that resulted in the formation of heavierelements from lighter elements?

Base your answers to questions 35 through 37 on the cross-sectional model below and the table on thefollowing page, and on your knowledge of Earth science. The model shows a reddish-orangesupergiant star. The layers in the model indicate where new chemical elements are forming fromexisting elements as temperature and pressure conditions increase with depth within the star. In eachlayer, atomic nuclei of the existing chemical element combine to form the new elements shown to theright of the arrow. The table shows the chemical symbols and names of selected elements in the star.

A) 3,200 K B) 6,000 K C) 10,500 K D) 18,000 K

35. What is the approximate surface temperature of this star during this stage of development?

A) less than the luminosity of the SunB) greater than the luminosity of most stars in the main sequenceC) approximately the same luminosity as a white dwarfD) approximately the same luminosity as Aldebaran

36. The luminosity of this star can best be described as

A) contact metamorphism B) internal crystallizationC) nuclear fusion D) radioactive decay

37. Which process represented in the model is occurring in each layer of this star to produce the newchemical elements?

A) Red Dwarfs B) White DwarfsC) Red Giants D) Blue Supergiants

38. Compared to other groups of stars, the group that hasrelatively low luminosities and relatively lowtemperatures is the

A) Sirius B) RigelC) the Sun D) Betelgeuse

39. Which star’s surface temperature is closest to thetemperature at the boundary between Earth’s mantleand core?

A) main sequence star with a temperature ofapproximately 4,000ºC and a luminosity of 100

B) main sequence star with a temperature ofapproximately 6,000ºC and a luminosity of 1

C) white dwarf star with a temperature ofapproximately 10,000ºC and a luminosity of0.01

D) blue supergiant star with a temperature ofapproximately 20,000ºC and a luminosity of700,000

40. According to the graph, the Sun is classified as a

A) 10 times B) 100 timesC) 1000 times D) 10,000 times

41. Approximately how many times larger is thediameter of the sun compared to the earth?

A) hotter and largerB) hotter and smallerC) cooler and largerD) cooler and smaller

42. Compared to the sun a white dwarf star is

A) Rigel B) Barnard’s StarC) Alpha Centauri D) Aldebaran

43. Which star has a higher luminosity and a lowertemperature than the Sun?

A) 0.08 - 0.5 MSun B) 10 - 150 MSun

C) 2 - 10 MSun D) 0.5 - 2 MSun

44. The schematic below shows the number of starsformed in each mass range for each star moremassive than 10 MSun.

What is the mass range of the most common stars?

45. Base your answer to the following question on the side-view model of the solar system in youranswer booklet and on your knowledge of Earth science. The planets are shown in their relative orderof distance from the Sun. Letter A indicates one of the planets.

Identify the process that occurs within the Sun that converts mass into large amounts of energy.

A) solar eclipses B) sun spotsC) solar storms D) black holes

46. The most observable phenomena in the "SolarCycle" is the appearance of

Base your answers to questions 47 and 48 on the diagram below and on your knowledge of Earthscience.

The diagram represents the inferred changes to the luminosity and color of the Sun throughout its lifecycle. The diagonal dashed line represents the main sequence stars. The numbers 1 through 5represent stages in the life cycle of the Sun.

A) Alpha Centauri B) Procyon BC) Barnard's Star D) Polaris

47. For other stars in our galaxy that go through a similar life cycle to our Sun, which star is currently inthe late stage of its life cycle?

A) white dwarf star B) gas cloud (nebula)C) main sequence star D) giant star

48. The Sun is inferred to be the most luminous when it is classified as a

A) cosmic background radiation in spaceB) parallelism of planetary axesC) radioactive dating of Earth’s bedrockD) life cycle of stars

49. Which evidence best supports the theory that theuniverse began with a massive explosion?

A) nuclear fusion B) conductionC) convection D) radioactive decay

50. Light and other forms of electromagnetic radiationare given off by stars using energy released during

A) hotter and brighter in stage 2, then cooler anddimmer in stage 3

B) cooler and dimmer in stage 2, then hotter andbrighter in stage 3

C) hotter and dimmer in stage 2, then cooler andbrighter in stage 3

D) cooler and brighter in stage 2, then hotterand dimmer in stage 3

51. Stars are believed to undergo evolutionary changesover millions of years. The flowchart below showsstages of predicted changes in the Sun.

According to this flowchart, the Sun will become

A) White Dwarf B) SupergiantC) Red Giant D) Main Sequence

52. What type of star is Polaris?

A) to expand as a red giant, undergo a novaoutburst and end as a white dwarf

B) to shrink to a white dwarf then eventuallyexpand to a red giant

C) become hotter and expand into a bluesupergiant

D) to become a black hole

53. The probable fate of our sun is

A) hotter than RigelB) more luminous than RigelC) closer than RigelD) larger than Rigel

54. To an observer on Earth, the Sun appears brighterthan the star Rigel because the Sun is

A) white B) redC) yellow D) blue

55. The coolest stars appear

A) nuclear fissionB) nuclear fusionC) combustionD) electrical generation

56. Most of the radiant energy released by the sunresults from the process of

A) less luminous and have a lower surfacetemperature

B) less luminous and have a higher surfacetemperature

C) more luminous and have a lower surfacetemperature

D) more luminous and have a higher surfacetemperature

57. Compared to the luminosity and surface temperatureof red main sequence stars, blue supergiants are

A) in the Red Dwarf region.B) in the Supergiant region.C) among the White Dwarfs.D) on the Main Sequence.

58. In the H-R diagram, 90 percent of all stars fall

A) main sequence starB) red giant starC) white dwarf starD) red dwarf star

59. The star Algol is estimated to have approximatelythe same luminosity as the star Aldebaran approximately the same temperature as the Rigel. Algol is best classified as a

A) Star A is hotter than star B.B) Star A is more distant than star B.C) Star A appears brighter in the sky than star B.D) Star A is larger than star B.

60. Two stars of the same color are plotted on an H-Rdiagram. Star A is more luminous than star B. Whichone of the following statements could explain this?

A) a red giant B) a white dwarfC) the sun D) a red dwarf

61. Which of the following stars is hottest?

Base your answers to questions 62 through 64 on the diagram below, which shows two possiblesequences in the life cycle of stars, beginning with their formation from nebular gas clouds in space.

A) explode in a supernova B) become a black holeC) change into a white dwarf D) become a neutron star

62. According to the diagram, a star like Earth’s Sun will eventually

A) nebula B) supernova C) red giant D) black dwarf

63. Stars like Earth’s Sun most likely formed directly from a

A) mass and size B) temperature and originC) luminosity and color D) luminosity and structure

64. According to the diagram, the life-cycle path followed by a star is determined by the star’s initial

A) in the Sun by fusionB) when water condenses in Earth's atmosphereC) from the movement of crustal platesD) during nuclear decay

65. The reaction below represents an energy-producingprocess.

The reaction represents how energy is produced

A) size B) shapeC) color D) brightness

66. An astronomer can estimate the temperature of a starby observing its

A) among the hottest starsB) among the smallest starsC) very uniqueD) about average in all respects

67. Compared to other stars, the sun is

A) about the same brightnessB) over 10,000 times brighterC) much redderD) much hotter

68. Compared to the sun, stars near the top of the H-Rdiagram are always

A) would all lie on the main sequenceB) would be all over the diagramC) would form a horizontal lineD) would form a vertical line

69. If we plot many stars on an H-R diagram, all withthe same luminosity but different temperatures, they

A) Barnard’s Star B) BetelgeuseC) Rigel D) Sirius

70. Which star is cooler and many times brighter thanEarth’s Sun?

A) It could be a main sequence star.B) It may be quite large.C) This is a typical characteristic of stars.D) There must be an error in measurement.

71. Measurements indicate that a certain star has a veryhigh luminosity (100,000 times that of our sun) andyet has a temperature that is cooler than the sun.What can you conclude about this observation?

A) a white dwarf B) a black holeC) a supernova D) a red giant

72. According to our present theories of stellarevolution, our sun will change next into

A) hotter and less luminousB) hotter and more luminousC) cooler and less luminousD) cooler and more luminous

73. Compared to the surface temperature and luminosityof massive stars in the Main Sequence, the smallerstars in the Main Sequence are

A) solar eclipsesB) solar flaresC) meteorites entering the atmosphereD) lunar eclipses

74. What celestial phenomenum most affects radiocommunication and other electrical atmosphericchanges for us on earth?

A) nuclear fusion B) heat transferC) gravitational pull D) radioactive decay

75. By which process do stars convert mass into greatamounts of energy?

A) the late phase for small mass starB) the remains of a larger star's explosionC) in the main sequence phaseD) early phases, soon after a star's formation

76. At which phase of its evolutionary life is a whitedwarf star?

A) Barnard's Star B) BetelgeuseC) Procyon B D) Sun

77. The diagram below represents possible stages in thelife cycle of stars.

Which star has the greatest probability of producinga supernova explosion?

A) white dwarf B) novaC) supernova D) black hole

78. When a star less massive than our sun consumes allof its nuclear fuel it will then become a

A) the sun B) a blue supergiantC) a white dwarf D) a red giant

79. Which of the following stars is least bright?

A) smaller, hotter, and less luminousB) smaller, cooler, and more luminousC) larger, hotter, and less luminousD) larger, cooler, and more luminous

80. Compared with our Sun, the star Betelgeuse is

A) 40 Eridani B B) SiriusC) Aldebaran D) Barnard's Star

81. Which star is more massive than our Sun, but has alower surface temperature?

A) insolation B) conductionC) nuclear fusion D) radioactive decay

82. Energy is produced within a star's core by theprocess of

Base your answers to questions 83 and 84 on the flowchart below and on your knowledge of Earthscience. The flowchart shows the evolution of stars.

83. Describe how the diameter and luminosity of a main sequence star change as the star becomeseither a giant or a supergiant.

84. Identify the force responsible for the contraction of a nebula (a gas cloud of molecules) to form aprotostar.

A) Spica, Rigel, Deneb, BetelgeuseB) Polaris, Deneb, 40 Eridani B, Proxima

CentauriC) Barnards Star, Alpha Centauri, Rigel, SpicaD) Procyon B, Sun, Sirius, Betelgeus

85. Which sequence of stars is listed in order ofincreasing luminosity?

A) hotter and more luminousB) hotter and less luminousC) cooler and more luminousD) cooler and less luminous

86. Compared to the temperature and luminosity of thestar Polaris, the star Sirius is

A) hotter and less luminousB) cooler and more luminousC) the same temperature and largerD) hotter and larger

87. Compared to the sun, Polaris is

A) more hydrogen and less heliumB) more helium and less hydrogenC) more oxygen and less carbonD) less oxygen and more carbon

88. As the sun ages it will be composed of

A) ageB) massC) sizeD) distance from our sun.

89. What factor below usually determines whether a starwill be on the main sequence?

A) hydrogen B) heliumC) carbon D) oxygen

90. The most abundant element on the sun is

A) at the upper left end of the main sequenceB) at the lower right end of the main sequenceC) at the upper right corner of the H-R diagramD) at the lower left corer of the H-R diagram

91. The smallest stars on a H-R diagram are found

A) Betelgeuse and Barnard's StarB) Rigel and BetelgeuseC) Alpha Centauri and the SunD) Sirius and Procyon B

92. Which two stars have the most similar luminosityand temperature?

A) blue B) redC) yellow D) white

93. Small cool stars would most likely appear to be

A) massB) percentage of heliumC) percentage of carbonD) apparent brightness

94. What factor from the choices below determineswhether a star will evolve into a white dwarf, aneutron star, or a black hole?

A) corona B) period of rotationC) magnetic field D) changing size

95. Sun spots are believed to be most closely related tothe sun's

A) comet B) planetC) star D) moon

96. Which object forms by the contraction of a largesphere of gases causing the nuclear fusion of lighterelements into heavier elements?

A) Earth's Moon B) Halley's cometC) Venus D) Polaris

97. Which object in space emits light because it releasesenergy produced by nuclear fusion?

A) Sun B) Alpha CentauriC) Betelgeuse D) Procyon

98. Which star has the greatest size?

A) compaction B) condensationC) radioactive decay D) nuclear fusion

99. Great amounts of energy are released in the core of astar as lighter elements combine and form heavierelements during the process of

A) As temperature decreases, luminosityincreases.

B) As temperature decreases, luminosity remainsthe same.

C) As temperature increases, luminosityincreases.

D) As temperature increases, luminosity remainsthe same.

100. Which statement describes the general relationshipbetween the temperature and the luminosity ofmain sequence stars?

A) 5,000ºC B) 10,000ºCC) 20,000ºC D) 30,000ºC

101. A Red giant star would most likely have atemperature of

A) they are more luminous but have the sametemperature

B) they are less luminous but have the sametemperature

C) they are hotter but have the same luminosityD) they are cooler but have the same luminosity

102. We know that red giant stars are larger in diameterthan the sun because

A) Deneb B) AldebaranC) Sirius D) Pollux

103. Which star is hotter, but less luminous, than Polaris?

A) nova B) pulsarC) supernova D) nebula

104. The explosion of a massive star near the end of itslife is known as a

A) main sequence regionB) red giant regionC) white dwarf regionD) quasar region

105. The region of the H-R diagram occupied by moststars is the

A) sun spotsB) the sun's coronaC) the sun's solar windsD) nothing of the sun, since it is totally blocked

by the moon

106. During a total solar eclipse one might view

A) fusion B) insolationC) conduction D) radioactive decay

107. Which process combines lighter elements intoheavier elements and produces energy within theSun and other stars?

A) the color of the starB) the actual visual brightness of the starC) the apparent brightness of the star compared to

our sunD) the speed of the star

108. The vertical axis of an H-R diagram relates to the

A) Proxima CentauriB) PolluxC) RigelD) 40 Eridani B

109. Which star is cooler and less luminous than theSun?

A) A B) B C) C D) D

110. The graph below represents the brightness andtemperature of stars visible from Earth.

Which location on the graph best represents a starwith average brightness and temperature?

A) Barnard’s Star, Polaris, Sirius, RigelB) Aldebaran, the Sun, Rigel, Procyon BC) Rigel, Polaris, Aldebaran, Barnard’s StarD) Procyon B, Alpha Centauri, Polaris,

Betelgeuse

111. Which list shows stars in order of increasingtemperature?

Answer KeyStar Life Cycle and Star Classification

1. A2. C3. –more

massive/larger/giantsize/supergiant –Spica emits energyat a greater rate than Barnard's Star.–hot- ter/greatersurface temperature–Spica is ablue-colored star.

4.

5. –Spica –- Sirius –Alpha Centauri –Barnard's Star –Proxima Centauri

6. Relative surfacetemperature:–Alderbaran'ssurface temperaturewill increase. –Itwill get hotter.- Relative luminosity:–Its luminosity willbe reduced.–Luminosity willdecrease.

7. B8. C9. C10. B11. A12. B13. A

14. A15. D16. A17. B18. A19. D20. C21. B22. A23. A24. A25. D26. B27. C28. D29. A30. A31. B32. A33. B34. D35. A36. B37. C38. A39. C40. B41. B42. B43. D44. A45. – fusion, – nuclear

fusion, – conversionof hydrogen tohelium/H to He

46. B47. B48. D49. A50. A51. D52. C53. A54. C55. B56. B57. D58. D59. A60. D61. B62. C63. A64. A65. A66. C67. D68. B69. C70. B71. B72. D73. C74. B75. A76. B77. B78. A79. C80. D

81. C82. C83. Diameter:

— increases —becomes largerLumino- sity:— increases —higher rate of energyemission — The starappears brighter.

84. — gravity —gravitationalattraction

85. D86. B87. C88. B89. A90. A91. B92. C93. B94. A95. C96. C97. D98. C99. D100. C101. A102. A103. C104. C105. A106. B107. A108. B

Answer KeyStar Life Cycle and Star Classification

109. A110. B111. A