Astronomy Related Multiple Choice Questions With Answers

Astronomy Questions Answers Part 3 Eduhyme

We know that the constellations are not true groups of stars but only appear that way from our solar systems. The stars within a constellation are at greatly varying distances.

This article is for people who want to learn basic astronomy without taking a formal course. It also can serve as a supplement knowledge in a classroom, tutored or home-schooling environment.

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This article contains an abundance of practice quiz, test and exam questions. They are all multiple choice questions and are similar to the sorts of questions used in standardized tests.

1. A solar flare can produce

(a) Disturbances in the Earth’s magnetic field.
(b) Lunar libration.
(c) A total solar eclipse.
(d) A dark spot on the Sun.
(e) A reddish glow on the Moon.

2. Longitudes are not assigned values greater than 180 degrees east or 180 degrees west because

(a) Doing so would result in a redundant set of coordinates.
(b) The King of England forbade it in the seventeenth century, and no one has contradicted him since.
(c) Galileo saw that such a thing could not possibly occur.
(d) 180 degrees represents a full circle.
(e) Oh, but they are! Latitudes are commonly assigned values greater than 180 degrees east or 180 degrees west.

3. The Sun’s declination is 0 degrees on

(a) January 21.
(b) July 21.
(c) October 21.
(d) December 21.
(e) None of the above dates.

4. The Moon’s diameter is

(a) About 1/81 that of the Earth.
(b) About 1/30 that of the Earth.
(c) About 1/4 that of the Earth.
(d) About the same as that of the Earth.
(e) Variable, depending on its phase.

5. Which of the following constellations consists of a group of stars early in their lifespans, and still shrouded in the gas and dust from which they formed?

(a) The Pleiades
(b) Orion
(c) Ursa Minor
(d) Pollux
(e) Bootes

6. In the southern hemisphere, the Sun’s right ascension is 12 hours on or around the twenty-first day of

(a) September.
(b) December.
(c) March.
(d) June.
(e) No month; the Sun ever reaches a right ascension of 12 hours in the southern hemisphere.

7. The reddish color of the Moon during a total lunar eclipse is caused by

(a) Sunlight passing through the Earth’s atmosphere.
(b) Sunlight reflected from the Earth back to the Moon.
(c) Sunlight scattered by particles in interplanetary space.
(d) Solar flares.
(e) Solar prominences.

8. If you were at the south geographic pole, the elevation of Polaris, the North Star, would be approximately

(a) -90°
(b) 0°.
(c) +90°
(d) 180°W.
(e) 180°E.

9. Scattered artificial light, such as that produced by the lights of a large city,

(a) obscures many of the dimmer stars and constellations, which can be seen easily from locations in the outback.
(b) Causes the Moon to appear larger than it really is.
(c) Affects star visibility near the zenith more than star visibility near the horizon.
(d) Has no effect on stargazing whatsoever.
(e) Renders the dimmest stars more visible than they would be in the outback.

10. If Orion, the hunter, appears to be standing upright in the southern sky on a January evening as seen from New Hampshire, then at the same time, to view¬ers in Santiago, Chile, the hunter is

(a) standing upright in the northern sky.
(b) Tying on his side in the northern sty.
(c) Standing on his head in the northern sky.
(d) Invisible because the seasons in the southern hemisphere are inverted with respect to the seasons in the northern hemisphere.
(e) Invisible because it would never rise above the horizon.

11. The constellation Octans, near the south celestial pole, can be seen rising in the east on evenings in the month of

(a) April.
(b) July.
(c) October.
(d) January.
(e) None of the above

12. The relatively dark, central part of a sunspot is called the

(a) Core.
(b) Ecliptic.
(c) Pole.
(d) Umbra.
(e) Synodic.

13. Assuming that interstellar travel is possible and that humans will do it someday, the constellations will not be usable by the captains of interstellar space ships because

(a) Stars are invisible at warp speeds.
(b) The constellations have their characteristic shapes only from the vantage point of our solar system and its vicinity.
(c) All the stars will have moved to new positions and the present constellations will no longer exist.
(d) They do not radiate electromagnetic fields of the proper type.
(e) Wrong assumption! The constellations will be perfectly good navigational tools for long-distance interstellar travel.

14. Meridians on the Earth

(a) Are circles centered at the equator.
(b) Are circles centered at the south pole.
(c) Are half circles connecting the north and south poles.
(d) Are half circles parallel to the equator.
(e) Are straight lines passing through the Earth’s physical center.

15. At which of the following times of year would the number of hours of daylight change the least rapidly from one day to the next?

(a) Late June
(b) Late August
(c) Early October
(d) Early March
(e) Early April

16. The angular diameter of the Moon, considered as a whole and as viewed from the Earth, is

(a) About Vs the angular diameter of the Earth.
(b) About V2 the angular diameter of the Sun.
(c) Largest at apogee, and smallest at perigee.
(d) Tilted about 5 degrees with respect to the ecliptic.
(e) About the same as the angular diameter of the Sun.

17. How many hours of right ascension are there in 30 degrees of arc, measured along the ecliptic?

(a) One hour
(b) Two hours
(c) Three hours
(d) Four hours
(e) Six hours

18. Which constellation, easily visible at temperate latitudes in both the northern and southern hemispheres, is also known as the hunter?

(a) Hercules
(b) Libra
(c) Orion
(d) Pollux
(e) Ursa Major

19. An effect of libration is:

(a) That the Moon’s orbit is not a perfect circle.
(b) To accelerate solar particles as they encounter the Earth’s magnetic field.
(c) To cause the tides to lag the gravitational effects that produce them.
(d) To let us see slightly more than half the Moon’s surface.
(e) To allow viewing of the solar corona during a total solar eclipse.

20. The summer solstice in London, England, occurs within a day of

(a) March 21.
(b) June 21.
(c) September 21.
(d) December 21.
(e) None of the above

21. At the time of the first-quarter moon,

(a) The Earth is directly between the Sun and the Moon.
(b) The Moon is directly between the Sun and Earth.
(c) The Sun is directly between Earth and the Moon.
(d) The Moon is 90 angular degrees from the Sun in the sky.
(e) The Moon is 180 angular degrees from the Sun in the sky.

22. Which of the following constellations lies in the same direction as the center of our galaxy?

(a) Cancer
(b) Ursa Minor
(c) Gemini
(d) Orion
(e) Sagittarius

23. From which vantage point on the Earth would the star Sirius rise in the west and set in the east?

(a) The far northern hemisphere
(b) The North Pole
(c) The equator
(d) The far southern hemisphere
(e) Nowhere

24. What do the two stars Epsilon Eridani and Tau Ceti have in common?

(a) They are both red giants.
(b) They are members of a double-star system.
(c) They have both been suggested as possibly having Earthlike planets.
(d) They are both in the process of formation.
(e) Nothing; these are the names of constellations, not stars.

25 As seen from a multitude location in the southern hemisphere at around sunset, the first-quarter moon

(a) Would be in the northern sky.
(b) Would be in the southern sky.
(c) Would be rising in the east.
(d) Would be beneath the horizon and therefore not visible.
(e) Might or might not be visible depending on the season of the year.

26. The Sun’s declination is approximately +90° on or around the twenty-first day of

(a) September.
(b) December.
(c) March.
(d) June.
(e) No month; the Sun never reaches a declination of +90°.

27. The brightest star in the sky, other than the Sun, is

(a) Procyon.
(b) Deneb.
(c) Rigel.
(d) Sirius.
(e) Aldebaran.

28. Suppose that we make a scale model of the Earth-Moon system. The Earth’s is represented by a beach ball 1 meter in diameter. The Moon would best be represented as:

(a) A basketball 30 meters away.
(b) A baseball 5 meters away.
(c) Another beach ball 100 meters away.
(d) A marble 3 meters away.
(e) Another ball, but we need more data to know how big it should be and how far from the beach ball to place it.

29. Azimuth is essentially the same thing as

(a) Celestial longitude.
(b) Right ascension.
(c) Compass bearing.
(d) Elevation.
(e) Declination.

30. In the southern hemisphere, azimuth 0° is sometimes considered to be

(a) east.
(b) West.
(c) South.
(d) At the zenith.
(e) At the nadir.

31. The Sun’s rotational period, averaged between the poles and the equator, is roughly

(a) The same as the period of the Moon’s orbit around the Earth.
(b) The same as the Earth’s rotational period.
(c) One synodic day.
(d) Synchronized with the tides.
(e) Synchronized with the equinoxes.

32. At the north celestial pole,

(a) None of the observed constellations are circumpolar.
(b) The stars all stay above the horizon for 11 hours and 58 minutes a day and stay below the horizon for the other 11 hours and 58 minutes.
(c) Half the constellations are circumpolar.
(d) All the observed constellations are circumpolar.
(e) Polaris is exactly on the northern horizon.

33. Suppose that you are in Calcutta, India, on March 21. For how long is the Sun above the horizon that day, measured with respect to the center of its disk?

(a) Much longer than 12 hours
(b) A little longer than 12 hours
(c) Exactly 12 hours
(d) A little less than 12 hours
(e) Much less than 12 hours

34. The constellations as we know them today would no longer exist if we were to travel in time

(a) 100 years into the future.
(b) 200 years into the future.
(c) 300 years into the future.
(d) 400 years into the future.
(e) The constellations would appear the same as seen from all the above time- journey destinations.

35. Magellanic Clouds are

(a) high-altitude weather phenomena visible long after sunset.
(b) Vast tracts of interstellar dust.
(c) A part of the Sun’s corona.
(d) Caused by solar flares.
(e) None of the above.

36. The Sun derives its energy primarily from

(a) Hydrogen combustion.
(b) Hydrogen fusion.
(c) matter-antimatter reactions.
(d) Nuclear fission.
(e) Gravitational pressure.

37. From April 1 to July 1, as viewed at 10:00 P.M. from a multitude northern place such as Colorado, the circumpolar constellations appear to rotate

(a) 90 degrees clockwise.
(b) 90 degrees counterclockwise.
(c) 180 degrees.
(d) 0 degrees; they are in the same positions.
(e) By some amount, but we need more information to quantitatively answer this question.

38. In a few minutes on a clear, starry night, a star at the zenith will move toward the

(a) north celestial pole.
(b) South celestial pole.
(c) Vernal equinox.
(d) Celestial equator.
(e) None of the above.

39. As seen from the Earth’s equator, Polaris is approximately how many angular degrees from the zenith?

(a) 0°
(b) 30°
(c) 60°
(d) 90°
(e) There is not enough information given here to answer this.

40. The circumference of the ninetieth parallel in the northern hemisphere is

(a) The same as that of the equator.
(b) Half that of the equator.
(c) one-third that of the equator.
(d) Zero because it is the north geographic pole.
(e) Impossible to determine without more information.

41. The polar ice caps of Mars consist of

(a) Methane and ammonia ice.
(b) Frozen nitrogen.
(c) Frozen water and carbon dioxide.
(d) White sand exposed by the action of dust storms.
(e) Clouds in the upper atmosphere.

42. A shepherd moon

(a) Tends to grow in size by accumulating stray meteors and comets.
(b) acts to keep a planetar}? Ring from spreading out.
(c) Has several smaller moons orbiting around it.
(d) Gets its name from the fact that shepherds once used it to keep track of their sheep.
(e) is another name for a full moon.

43. If an object reflects one-quarter of the light that strikes it, then its albedo is approximately

(a) 25.
(b) 2.5.
(c) 0.25.
(d) 0.40.
(e) 4.00.

44. The notion that the Earth is a huge, living cell is known as

(a) The geobiological theory.
(b) The Gaia hypothesis.
(c) The tidal theory.
(d) The geogenetic theory.
(e) Nothing! No one has ever had such an idea.

45. The full phase of an inferior planet takes place at and near

(a) Superior conjunction.
(b) Inferior conjunction.
(c) Superior opposition.
(d) Inferior opposition.
(e) No time; inferior planets never appear in full phase.

46. The Roche limit of a planet is

(a) The smallest orbital radius a moon can have without being broken up by the parent planet’s gravity.
(b) The minimum temperature at which oxygen in the atmosphere of a planet can exist in a gaseous state.
(c) The maximum axial tilt a planet can have in order to be a hospitable place for the evolution of life.
(d) The smallest radius a planet can have and still manage to hold down an atmosphere.
(e) The maximum amount of ultraviolet radiation that can reach a planet’s surface without killing the living things on it.

47. Deimos is

(a) One of the moons of Mars.
(b) One of the volcanoes on Mars.
(c) The highland region on Venus.
(d) One of the moons of Venus.
(e) One of the moons of Mercury.

48. The Sun is closest to Earth during the southern-hemispheric

(a) Spring.
(b) Summer.
(c) Fall.
(d) Winter.
(e) Irrelevant! The Sun is always the same distance from the Earth.

49. The layer of Earth just beneath the crust is called the

(a) Basaltic layer.
(b) Ferromagnetic layer.
(c) Mantle.
(d) Outer core.
(e) Volcanic layer.

50. The so-called greenhouse gases

(a) Help heat to escape from a planet.
(b) Increase ultraviolet radiation reaching a planet’s surface.
(c) Block ultraviolet radiation.
(d) Tend to trap heat in a planet’s atmosphere.
(e) Keep Earth from becoming like Venus.

51. Ozone gas is known for its

(a) tendency to block ultraviolet radiation.
(b) Environmentally destructive effects.
(c) Greenhouse properties.
(d) Role in the ice ages.
(e) Presence in low-level clouds.

52. The lack of a substantial magnetic field around Mars

(a) Allows the existence of an ionosphere similar to that of Earth.
(b) Allows an ozone layer to form in the Martian atmosphere.
(c) Lets high-speed subatomic solar particles reach the surface.
(d) Is the result of a magnetically polarized iron and nickel core.
(e) Is the result of intense volcanic activity.

53. Uranus is

(a) About one-quarter the diameter of Earth.
(b) Slightly smaller than Earth.
(c) About the same diameter as Earth.
(d) Slightly larger than Earth.
(e) About four times the diameter of Earth.

54. On an Earth desert at high altitude, the temperature difference between day and night is considerable because

(a) Sand retains heat well.
(b) The wind blows hard.
(c) Sand does not retain heat well.
(d) There is almost no wind.
(e) The air is thick.

55. The orbit of Venus is

(a) Retrograde with respect to the orbits of the other planets.
(b) Nearly a perfect circle.
(c) slanted at 98 degrees relative to Earth’s orbit.
(d) An eccentric ellipse.
(e) in sync with its rotation, so it always keeps the same side facing the Sun.

56. A manned space vessel would not be advised to enter a low orbit around Jupiter because

(a) The temperature is extremely low.
(b) There is not enough sunlight to navigate.
(c) The radiation reaches dangerous or deadly levels.
(d) There is no ozone layer.
(e) The planet spins rapidly on its axis.

57. Which of the following pairs of planets are both closer to the Sun than Mars?

(a) Mercury and Earth
(b) Earth and Saturn
(c) Saturn and Uranus
(d) Venus and Jupiter
(e) Earth and Neptune

58. The atmospheric pressure on the surface of Venus

(a) is near zero because Venus has almost no atmosphere.
(b) is somewhat less than the pressure at the surface of Earth.
(c) is about the same as the pressure at the surface of Earth.
(d) is slightly greater than the pressure at the surface of Earth.
(e) is much greater than the pressure at the surface of Earth.

59. Which of the following pairs of planets are almost exactly the same sizes?

(a) Mercury and Jupiter
(b) Venus and Mars
(c) Mars and Jupiter
(d) Uranus and Neptune
(e) Neptune and Pluto

60. When Jupiter is at inferior conjunction,

(a) it appears full.
(b) it appears half full.
(c) it appears as a crescent.
(d) it transits the Sun.
(e) No! Jupiter never attains an inferior conjunction.

61. On a long journey in interplanetary space, artificial gravity might be provided by

(a) Special pressure suits.
(b) Vigorous daily exercise.
(c) Rotation of the living quarters in the vessel.
(d) A massive slab of metal in the back of the ship.
(e) Nothing; there is no such thing as artificial gravity.

62. The term precession refers to

(a) The distortion of the geomagnetic field by the solar wind.
(b) The variation of Jupiter’s rotation rate with latitude.
(c) The wobbling of the Moon so that we see more than half of it over time.
(d) The wobbling of Earth’s axis over long periods of time.
(e) The ionization of Earth’s upper atmosphere.

63. A caldera is

(a) A mountain.
(b) A valley.
(c) An escarpment.
(d) A dried-up riverbed.
(e) A volcanic crater.

64. On the planet Venus, Ishtar is

(a) A highland region.
(b) A volcano.
(c) A crater.
(d) An escarpment.
(e) Another name for the cloud deck.

65. The layer of Earth’s atmosphere in which weather occurs is known as the

(a) ionosphere.
(b) Isosphere.
(c) Troposphere.
(d) Stratosphere.
(e) Thermosphere.

66. Since the formation of the Solar System, the interior of Mars is believed to have cooled off faster than the interior of Earth because

(a) Mars is farther from the Sun than is Earth.
(b) Mars has a thinner atmosphere than does Earth.
(c) Mars rotates faster than Earth.
(d) The surface-area-to-volume ratio is larger than that of Earth because Mars itself is smaller.
(e) No! Mars is believed to have cooled off more slowly than the Earth.

67. The light regions in Jupiter’s atmosphere, as seen through a telescope on Earth or from a great distance away in space, are

(a) Whitecaps on the liquid surface.
(b) Snow.
(c) The tops of high clouds.
(d) Blowing sand.
(e) Volcanic eruptions.

68. Some scientists think that the Pluto Charon system ought to be classified as

(a) An asteroid.
(b) A star.
(c) A double comet.
(d) A ring system.
(e) A shepherd moon.

69. Mercury does not often present itself well for observation because

(a) It is extremely small.
(b) It is extremely dense.
(c) It is close to the Sun.
(d) It is far from the Sun.
(e) It always shows us its dark side.

70. The temperature on the dark side of Mars

(a) Is below 0°C.
(b) Is about the same as the temperature on the daylight side.
(c) Is a comfortable room temperature.
(d) is hot enough to melt lead.
(e) is near absolute zero.

71. Jupiter’s Great Red Spot is

(a) A volcano.
(b) A mountaintop.
(c) An escarpment.
(d) A crater.
(e) A weather system.

72. The upper clouds of Venus rush around the planet, completing one revolution in approximately

(a) One Venus day.
(b) One Venus year.
(c) 24 Earth hours.
(d) Four Earth days.
(e) No! Venus has no clouds.

73. Saturn’s brightness, as we see it from Earth, is affected by

(a) The angle at which Saturn’s rings are presented to us.
(b) The distance of Saturn from the Sun.
(c) The tilt of Saturn on its axis.
(d) The temperature on Saturn’s surface.
(e) The distance of Earth from the Sun.

74. The most abundant gas in Earth’s atmosphere is

(a) Oxygen.
(b) Hydrogen.
(c) Helium.
(d) Carbon dioxide.
(e) Nitrogen.

75. An escarpment is

(a) A crater.
(b) A volcano.
(c) A tiny planetary Moon.
(d) A moon that has escaped from a planet.
(e) A cliff.

76. The butterfly effect is another name for the fact that

(a) Minor events always have small consequences.
(b) Major events always have large consequences.
(c) Minor events never have any consequences.
(d) Seemingly insignificant events can have large consequences.
(e) Life cannot exist on Mars.

77. When Mars is at an ideal opposition,

(a) It is closer to Earth than at any other time.
(b) It is farther from Earth than at any other time.
(c) It is brighter than Venus.
(d) It is invisible because the light of the Sun washes it out.
(e) It appears in a crescent phase.

78. The most abundant gas in the atmosphere of Mars is

(a) Oxygen.
(b) Nitrogen.
(c) Methane.
(d) Carbon dioxide.
(e) Carbon monoxide.

79. Which of the following planets has not been observed to have rings?

(a) Mars
(b) Jupiter
(c) Saturn
(d) Uranus
(e) Neptune

80. Mercury is believed to have a core consisting of

(a) Granite.
(b) Water.
(c) Solid metallic hydrogen.
(d) Molten silicate rock.
(e) Iron.

81. The term epicycle refers to

(a) The motion of a planet with respect to the stars.
(b) The variation in the Moon’s orientation with respect to Earth.
(c) The speed of a planet’s revolution around the Sun.
(d) The wobbling of Earth on its axis.
(e) A component of a planetary orbit according to Ptolemy.

82. Which of the following planet has the most known moons?

(a) Mercury
(b) Mars
(c) Saturn
(d) Uranus
(e) Pluto

83. An accretion disk is

(a) A ring around a planet such as Saturn.
(b) A region around a planet in which orbits are stable.
(c) The plane of the orbits of the planets around a star.
(d) A rotating, flat cloud of matter from which planets form around a star.
(e) a computer disk used for storing position data for celestial objects.

84. Fill in the blank in the following sentence. The names of meteor showers derive from the positions of the ____________ in the sky, which tend to be the same, year after year, for any given meteor shower.

(a) Escarpments
(b) Originating comets
(c) Originating asteroids
(d) Radiants
(e) Focal points

85. Fill in the blank in the following sentence. The theory of __________, given sufficient time to operate, results in the evolution of life forms that are better and better suited to the particular environment in which they live.

(a) Natural selection
(b) Biological entropy
(c) Conservation of energy
(d) Thomas Malthus
(e) Planetary evolution

86. According to the geocentric theory

(a) The Earth revolves around the Sun.
(b) The Sun revolves around the Earth.
(c) The Moon revolves around the Sun.
(d) The distant stars are reflections of Earth.
(e) Everything is sitting still in the Universe.

87. A laser can be used in long-distance space communication when it is necessary to

(a) Direct the energy in a narrow beam.
(b) Use as wide a frequency range as possible.
(c) Spread the radio waves over a wide angle.
(d) Generate large amounts of intergalactic noise.
(e) Slow down the rate of data transmission.

88. Entropy has a tendency to

(a) Turn chaos into order.
(b) Equalize temperatures.
(c) Create life.
(d) Make stars shine.
(e) Make planets form from cosmic dust.

89. Thomas Malthus is known for his theory that

(a) The human population increases geometrically, but the food supply increases arithmetically at best.
(b) The human population increases arithmetically, but the food supply increases geometrically at best.
(c) Both the human population and the food supply increase geometrically.
(d) War ultimately will bring about the destruction of any technologically advanced civilization.
(e) A desire to travel among the stars is a characteristic of any intelligent species.

90. The Pluto-Charon system is unique in the sense that

(a) The planet and the moon always keep the same faces toward each other.
(b) The planet and the moon are the same size.
(c) The moon is larger than the planet.
(d) Both objects are believed to have once been moons of Neptune.
(e) They are much warmer than the other outer planets or their moons.

91. A comet might bum out because

(a) It falls into the Sun.
(b) A solar flare hastens the disintegration of its nucleus.
(c) It is struck by a small asteroid, which shatters its nucleus.
(d) Either a, b, or c take place.
(e) No! Comets never burn out.

92. Attempts to determine the number of advanced civilizations in the Milky Way galaxy have been carried out mathematically using

(a) Radio waves.
(b) Star charts.
(c) Optical telescopes.
(d) The Green Bank formula.
(e) The Malthusian formula.

93. The planet Venus has a retrograde orbit around the Sun

(a) Because it was knocked out of alignment long ago by a collision with a protoplanet almost as large as itself.
(b) Because it is influenced by the gravitational fields of Earth and Mercury.
(c) Because it is tilted on its axis by almost 180 degrees.
(d) Because it was originally from outside the Solar System and was captured by the Sun’s gravity after all the other planets were formed.
(e) No! The planet Venus does not revolve around the Sun in a retrograde manner, but in the same sense as all the other planets.

94. So-called minor collisions, small asteroids striking planets, have been suggested as a catalyst for

(a) Wiping out all life.
(b) The evolution of intelligent life.
(c) Creating dinosaurs.
(d) Adding oxygen to the atmosphere.
(e) Creating oceans.

95. The Milky Way galaxy contains about

(a) 20,000 stars.
(b) 200,000 stars.
(c) 2 million stars.
(d) 20 million stars.
(e) None of the above

96. Copernicus was one of the earliest astronomers to hypothesize that

(a) Earth revolves around the Sun.
(b) The stars revolve around the Sun.
(c) Epicycles exist within other epicycles.
(d) The planets are more distant than the stars.
(e) The Milky Way is not the only galaxy in the Universe.

97. Planetary moons almost always have rotation periods that correspond to their orbital revolution periods

(a) Because of tidal effects between the moon and the parent planet.
(b) Because the moons orbit in the plane of the parent planet’s equator.
(c) Because the moons were captured from interplanetary space by the parent planet’s gravity.
(d) Because the moons are perfect spheres.
(e) No! Planetary moons almost never have rotation periods that correspond to their orbital revolution periods.

98. When we say a celestial body has a low albedo, we mean to say that it is

(a) Relatively low in density.
(b) Relatively low in specific gravity.
(c) Nonspherical in shape.
(d) Relatively dark in appearance.
(e) not a good place for life to evolve.

99. When a planet or moon that has many craters is viewed from a distance, some craters have bright lines that run outward from the center. Such lines are called

(a) subcraters.
(b) Crateroids.
(c) Escarpments.
(d) Rift valleys.
(e) Rays.

100. The age of the Solar System is believed by most scientists to be approximately

(a) 4.6 million years.
(b) 4.6 billion years.
(c) 10 billion years.
(d) 200 billion years.
(e) 4.6 trillion years.