Our Solar System


Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.

1.   The oldest rocks found on Earth are about __________ years old.
 a.    10 billion
 b.   5.3 billion
 c.  4.6 billion
 d.   3.9 billion
 e.  6.2 million

  2.   Which of the following is not a characteristic of the terrestrial planets?
 a.   low average density
 b.  orbits inside the asteroids
 c.   craters in old surfaces
 d.   small diameters
 e.  very few satellites

 3.   A future news release might report that a new planet has been found around a star very similar to our sun. This
newly discovered planet is claimed to have a mass 40 times that of Earth and is located nearly 25 AU from the star it
orbits. Which of the following would be a reasonable prediction about this planet?

 I.       The planet will probably have a mean density of around 5 g/cm3.
 II.     The planet will probably have a radius of around five to ten times greater than
 III.    The planet will probably have several satellites.
 IV.    The planet will probably have a composition that is mostly hydrogen and helium.

 a.    I & IV
 b.  I, II, & III
 c.   II, III, & IV
 d.   I, II, & IV
 e.   I, II, III, & IV

 4.   A __________ is a solar system object that enters Earth's atmosphere and becomes very hot due to friction between
the object and Earth's atmosphere.
 a.    asteroid
 b.   meteor
 c.   comet
 d.   meteoroid
 e.  planetesimal

  5.   The age of the solar system is believed to be approximately 4.6 billions years based on the data from
 a.    samples of lunar rocks.
 b.  samples of Earth rocks.
 c.   samples of meteorites.
 d.  all of the above
 e.  none of the above.


 6.   Once a terrestrial planet had formed from a large number of planetesimals, heat from __________ could have melted it and allowed it to differentiate into a dense metallic core and a lower density crust.
 a. radioactive decay
 b. the sun
 c.  volcanic eruptions
 d. tidal forces
 e. impacts of small meteorites

 7.   The condensation sequence suggests that __________ should condense closest to the sun.
 a.    Jovian planets
 b.  metals and metal oxides
 c. silicates
 d.  ices of water, methane, and ammonia
 e.   low density materials

  8.   Condensation in the solar nebula probably led to the formation of
 a.   icy grains beyond the present orbit of Jupiter.
 b.   metallic grains near the present orbit of Mercury.
 c.  silicate grains near the present orbit of Earth.
 d.  all of the above
 e. none of the above


 9.   Protoplanets of the Jovian planets could have grown very hot from
 a.    heat for the sun.
 b.  radioactivity of light elements such as hydrogen and helium.
 c.   the in fall of material at high velocity.
 d.   tidal forces due to the sun.
 e.  collisions with large planetesimals.

 10.   If the terrestrial planets formed by homogeneous accretion, then
 a.    they formed an iron core first, and a silicate crust later.
 b.  the solar nebula changed during their fragmentation.
 c.   Earth's original atmosphere was rich in hydrogen.
 d.  the terrestrial planets should now have the same composition as the Jovian planets.
 e.  the terrestrials should have had several satellites each.

11.   The planets all lie in nearly the same plane resulting in a disk-like structure for the solar system. This disk-like
structure is believed to exist because
 a.    the original solar nebulae had a disk-like structure.
 b.   the bipolar flow from the young sun cleared all material out of the nebula except that
    in the disk.
 c.   Jupiter's gravity was great enough to pull all of the other planets to the plane of its
 d.    planetesimals settled into the plane of rotation of the solar nebula.
 e.  the sun's magnetic field slowed down the rotation of the solar nebula.

   12.   Which one of the following objects is most like the planetesimals that formed in the solar nebular?
 a. asteroids
 b.  Earth
 c. Saturn
 d. Venus
 e. the sun

13.   The large planetesimals would have grown faster than the smaller planetesimals because
 a.    they were moving faster in their orbits than the smaller planetesimals.
 b.   their stronger gravity would pull in more material.
 c.   there was more material located near them that could be accreted.
 d.  the smaller planetesimals were covered by a layer of material that was lost during
 e.  all of the above

14.   Accretion among the grains in the solar nebula would have been aided by
 a.    static electricity.
 b.  gravity.
 c.  high-velocity collisions
 d.  all of the above
 e.  none of the above

15.   Based on current observations, __________ has a heavy element core, and a very dense, deep atmosphere made mostly of hydrogen.
 a. Uranus
 b.  Pluto
 c.  Venus
 d.  an asteroid
 e. a meteor

16.   If a star is found with five planets orbiting it, and a process like that described in the solar nebula theory formed the planets, which of the planets would be expected to have the greatest uncompressed density?
 a.  The one farthest from the star.
 b.  The one with the greatest mass.
 c.  The one with the greatest radius.
 d.  The one closest to the star.
 e.  The one that has liquid water on its surface.

 17.   The current atmosphere of Earth is believed to be
 a.    the remnants of the original gas from the solar nebula attracted by the protoplanet.
 b.  the result of the melting and vaporizing of the glaciers from the last ice age.
 c.   composed primarily of hydrogen and helium.
 d.  composed of gases that were baked from the rocks sometime after the planet formed.
 e.  the result of a collision between the sun and another star.

18.   The most important effect in clearing the solar nebula of gas and dust was
 a.    impacts by planetesimals.
 b.   the solar wind.
 c.   the sun's magnetic field.
 d.   the asteroid belt.
 e.   radiation pressure.

19.   The uncompressed mass of a planet in our solar system
 a.    is greatest for the Jovian planets.
 b.    is greatest for the planets closest to the sun.
 c.    is greatest for the planets furthest from the sun.
 d.  is greatest for the planets with the largest mass.
 e.  is greatest of the planet with the largest radius.

  20.   51 Pegasi is an important object because
 a.    it is a pulsar with planets orbiting around it.
 b.   it is a star with a planet that is known to support intelligent life.
 c.  it is the largest satellite of Jupiter.
 d. it is the largest known asteroid.
 e.  it is the first star like our sun that was found to have a planet orbiting it.

 21.   Which of the following observations would support the solar nebula theory over the passing star hypothesis?
 a.    Proving that most of the sun-like stars near the sun also have planets orbiting them.
 b.   Proving that none of the stars near the sun has planets orbiting them.
 c.   Finding a planet located beyond the orbit of Pluto.
 d.   Finding a meteorite whose age proved to be greater than 4.6 billion years.
 e.   Proving that Mercury has the same uncompressed density as Earth.

 22.   On a photograph of the moon, the moon measures 30 cm in diameter and a small crater measures 0.2 cm. The moon's physical diameter is 1738 km, what is the physical diameter of the small crater?
 a.  about 1738 km
 b.   about 12 km
 c.   about 520 km
 d.  about 350 km
 e.  about 3.5 km

 23.   The speed of the solar wind is approximately 400 km/s and the distance from the sun to Saturn is 9.5 AU (1 AU = 1.5 x 108 km). How long does it take a particle in the solar wind to reach Saturn?
 a. about 4.1 hours
 b.   about 4.1 days
 c.   about 41 days
 d.   about 4.1 years
 e.  about 41 years
 24.   Suppose that Mercury grew to its present size in 1 million years through the accretion of particles averaging 100 g each. On average how many particles did Mercury capture each second? Note: Mercury has a mass of 3.3 x 1023 kg and a radius of 2439 km.
 a.  about 24 particles per second
 b. about 3.3 « 1021 particles per second
 c. about 67 particles per second
 d.    about 100 million particles per second
 e.   about 100 billion particles per second
25.   The diagram below illustrates the radioactive decay of Potassium (40K), which has a half-life of 1.3 billion years. If a lunar rock is found that currently contains 5 grams of 40K, and it is determined that the sample contained 20 grams when it was formed, how old is the lunar rock?

 a.    6.5 billion years
 b.  19.5 billion years
 c.   2.6 billion years
 d.  3.9 billion years
 e.  4.6 billion years

 26.   Both Jupiter and Saturn
 a.    have liquid metallic hydrogen in their interiors.
 b.  have rings.
 c.  emit more energy than they absorb from the sun.
 d.  have belt and zone circulation.
 e.  all of the above

27.   Belt and zone circulation
 a.    has been observed only on Jupiter.
 b.    is caused by the planet's magnetic field.
 c.  is caused by rising and sinking gases.
 d.  is more obvious on Saturn than Jupiter.
 e   explains the formation of Cassini's division.

 28.   Jupiter does not have
 a.    a hot interior.
 b.  convection occurring in its atmosphere.
 c.  crustal plates on its surface.
 d. a dynamo effect.
 e.  any rings.

29.   Europa has few craters because
 a.    it is protected from impacts by Jupiter's gravity.
 b.   it does not have a solid surface.
 c.   it has erased craters nearly as fast as they have formed.
 d.   its surface is not strong enough to support craters.
 e.    it keeps one face always pointed toward Jupiter which screens it from incoming

30.   Saturn's atmosphere is
 a.    more brightly marked than Jupiter's.
 b.   rich in free oxygen.
 c.   hazy above the clouds.
 d.    all of the above
 e.    none of the above

31.   Saturn's rings are
 a.    composed of ice particles.
 b.    in the plane of the planet's equator.
 c.    within the planet's Roche limit.
 d.    all of the above
 e.    none of the above

 32.   Saturn's F ring and the rings of Uranus are similar in that
 a.    they are made of dark material.
 b.    they are made of icy material.
 c.    they are found near large moons.
 d.    they show well defined spokes.
 e.    they are very narrow.

33.   Though Titan is small, it is able to retain an atmosphere because
 a.    it is very cold.
 b.    it is very dense.
 c.    it rotates very slowly.
 d.    it attracts gas from the solar wind.
 e.    it has a very strong magnetic field.


34.   __________ in Saturn's rings is/are produced by the gravitational interaction of Mimas with the particles in the rings
and appears as a large gap in the rings.
 a.    Spokes
 b.    Spiral density waves
 c.    Bending waves
 d.    The Io torus
 e.    Cassini's division

35.   The old surfaces of icy satellites
 a.    appear dark in color with few impact craters.
 b.    appear dark in color with many impact craters.
 c.    appear very bright because ice is very reflective.
 d.    generally show long bright grooves and a modest number of impact craters.
 e.    generally have small volcanoes that are active.
36.   Which of the Galilean satellites are geologically active?
 a.    Io and Callisto
 b.    Ganymede and Titan
 c.    Titan and Callisto
 d.    Europa and Io
 e.    Ganymede and Callisto

37.   The graph below indicates the temperature of Saturn's atmosphere as a function of distance from the upper cloud layer. Water will condense to form droplets at a temperature of approximately 270 K in the atmosphere of Saturn. At what distance from the upper cloud layer will clouds of water vapor form?

 a.    -250 km
 b.    -150 km
 c.    0 km
 d.    150 km
 e.    250 km
 38.   Liquid metallic hydrogen
 a.    is found in the outer atmosphere of Jupiter.
 b.    is believed to exist on the surface of Titan.
 c.    is believed to exist on Io.
 d.    does not conduct electricity very well.
 e.    none of the above

39.   Which of the following objects may have organic particles on its surface as a result of the interaction of sunlightwith methane in its upper atmosphere.
 a.    Io
 b.    Titan
 c.    Hyperion
 d.    Ganymede
 e.    Metis
40.   In what way is the rocky material of Jupiter's core different from the rocks found on Earth?
 a.    It is much cooler because Jupiter is further from the sun.
 b.    It contains more liquid water.
 c.    It is much hotter and more dense because of the extreme pressure at the core of
 d.   It is composed of iron and nickel because this material will settle to the core.
 e.    It is composed entirely of ices that have frozen into a large rock like structure.

 41.   The excess heat produced by Jupiter and Saturn is the result of
 a.    nuclear reactions in their liquid metallic hydrogen cores.
 b.    radioactive decay.
 c.    hot molten lava rising to the surface.
 d.    the continual slow contraction of each planet.
 e.    the large number of meteorite and comet impacts that occur each year.
 42.   The atmosphere(s) of __________ contain(s) mostly nitrogen with traces of methane.
 a.    Uranus
 b.  Neptune
 c.   Miranda
 d.    Pluto
 e.    Uranus and Neptune

43.   The rotation of Uranus is peculiar in that
 a.    it is much slower than is typical for Jovian planets.
 b.    it is much faster than is typical for Jovian planets.
 c.    the equator rotates much faster than the poles.
 d.    the axis is nearly parallel to the plane of its orbit.
 e.    it can not be measure because Uranus has no surface features.

 44.   Uranus and Neptune do not contain liquid metallic hydrogen because they
 a.    are not massive enough.
 b.    do not contain enough hydrogen.
 c.    rotate too slowly.
 d.    are too far from the sun.
 e.    have magnetic fields that are much too weak.
45.   Belt-zone circulation is not easily visible on Uranus because
 a.    no clouds form in the pure hydrogen atmosphere.
 b.    there is no differential rotation.
 c.   clouds form very deep in the atmosphere.
 d.    the atmosphere is stirred by cyclonic circulation.
 e.   there is no liquid metallic core.

46.   The magnetic fields of Uranus and Neptune are peculiar in that they are
 a.    highly inclined to the axis of rotation.
 b.   very strong.
 c.    linked to the solar wind.
 d.   produced by disturbances caused by the orbits of the moons.
 e.   all of the above

47.   The rings of Uranus were discovered
 a.    during an occultation of a star.
 b.    during an eclipse of one of the moons by the rings.
 c.    during an eclipse of Uranus by the rings.
 d.    as Uranus and the rings passed behind Jupiter.
 e.    by Voyager 1.

48.   The narrowness of the rings of Uranus and Neptune is believed to be caused by
 a.    gravitational interactions between ring particles.
 b.   a spiral density wave which confines them.
 c.    the magnetic field which holds them in place.
 d.   the smaller mass of Uranus and Neptune as compared to that of Saturn.
 e.    small shepherd moons that orbit near the rings.
49.   We can be sure the particles in the rings of Neptune are very small because
 a.    the rings are faint in forward scattered light.
 b.    the rings are bright in forward scattered light.
 c.    only small particles are produced in comet impacts with larger moons.
 d.    the magnetic field of Neptune would quickly force large particles out of the rings.
 e.    the larger particles would be quickly destroyed by impacts with the shepherd

50.   Which of the following are found on Triton?
 a.    craters.
 b.    flooded basins.
 c.    eruptions of nitrogen through vents in the surface.
 d.    a nitrogen atmosphere.
 e.    all of the above

 51.   The graph below plots the escape velocity of several solar system objects along the vertical axis and the surface temperature along the horizontal axis. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the objects in this diagram has the greatest surface temperature?

 a.    Ganymede
 b.    Pluto
 c.    Titan
 d.    Triton
 e.    Miranda
 52.   __________ is a satellite of Pluto.
 a.    Miranda
 b.    Charon
 c.    Triton
 d.    Krypton
 e.    Nereid
53.   The diagram below shows a cross section of the interior of Uranus. Which of the regions do current computer models suggest is composed primarily of water?

 a.    region 1
 b.   region 2
 c.    region 3
 d.    all of the regions
 e.    none of the regions

54.   Uranus and Neptune appear blue because
 a.    their atmospheres absorb blue light very efficiently.
 b.    both of them have very small masses for Jovian planets.
 c.    their surfaces are covered with water and their clouds are very thin
 d.    their atmospheres absorb red light very efficiently.
 e.    the wind speeds are very high and show a strong blue shift.

55.   Nereid orbits Neptune in a highly elliptical orbit and Triton has a retrograde orbit around Neptune. This information suggests that
 a. Neptune formed out of the solar nebula in much the same manner as the other Jovian
 b.    Pluto was probably a moon of Neptune that escaped.
 c.    Triton and Nereid are both captured objects from the inner solar system, probably the
    asteroid belt.
 d.    Triton and Nereid may both have suffered major impacts that radically changed their
 e.    Triton and Nereid should both have relatively strong magnetic fields.

 56.   Ariel has a bright surface and grooves 10 km deep. Based on this, it can be concluded that
 a.    Ariel has a fairly old surface.
 b.    Ariel has a fairly young surface.
 c.    Ariel has a thin atmosphere.
 d.    Ariel is very far from its parent planet, Uranus.
 e.    a and d

 57.   The graph below plots the escape velocity of several solar system objects along the vertical axis and the surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the gases potted in this diagram could be retained by Miranda?

 a.    only CO2
 b.    only NH3
 c.    CO2, NH3, and O2
 d.    all of them
 e.    None of them

58.   Pluto's density is 1.8 g/cm3. This implies that
 a.    Pluto has a large iron-nickel core.
 b.    Pluto is about 50% water and 50% rocky material.
 c.    Pluto should have a magnetic field about one-third as strong as Earth's.
 d.    Pluto is still geologically active.
 e.    Pluto probably has a small ring system that hasn't yet been detected.

59.   A bit of matter that enters Earth's atmosphere and survives to reach the ground is called
 a.    a meteor.
 b.    a meteoroid.
 c.    a meteorite.
 d.    a minor planet.
 e.    an asteroid.

60.   Chondrites are meteorites that have
 a.    never been heated.
 b.    been heated sufficiently to release the volatiles it contained.
 c.    been heated sufficiently to melt the chondrules.
 d.    been completely melted.
 e.    entered Earth's atmosphere but will be destroyed before reaching the ground.

61.   A meteor shower is produced when
 a. a large number of sporadic meteors are observed.
 b.    Earth passes through the asteroid belt.
 c.    massive particles are carried outward from the sun by the solar wind and enter Earth's atmosphere.
 d.    Earth passes through the orbital path of a comet.
 e.    meteors cause condensation in the upper atmosphere that leads to early morning   rains.

62.   Most of the asteroids orbit the sun in a belt between the orbits of
 a.    Venus and Earth.
 b.    Earth and Mars.
c.    Jupiter and Saturn.
d.    Mercury and Venus.
e.    Mars and Jupiter.

63.   The __________ meteorites are believed to have formed in the mantle of a large asteroid.
 a.    chondrite
 b.    iron
 c.    achondrite
 d.    carbonaceous chondrite
 e.    chondrule
64.   The __________ meteorites could have formed in the crust of a large asteroid that was later fragmented.
 a.    chondrite
 b.    iron
 c.    achondrite
 d.    M-type
 e.    chondrule

65.   An asteroid could produce an iron core and a silicate mantle if it
 a.    differentiated.
 b.    outgassed.
 c.    condensed.
 d.    accreted.
 e.    sublimed.


66.   The gas tail of a comet always
 a.    trails behind the head along the orbital path.
 b.    extends ahead of the head along the orbital path.
 c.    points toward the sun.
 d.    points away from the sun.
 e.    points perpendicular to the orbital path

67.   The short-period comets do not have randomly oriented orbits because
 a.    they are affected by the sun's gravity.
 b.    they are affected by the solar wind.
 c.    they formed in the Kuiper Belt, a belt shaped region in the plane of the solar system.
 d.    their orbits are altered by the drag of their tails in the solar wind.
 e.    they all were originally objects ejected from the asteroid belt.

68.   One theory suggests that the bodies in the Oort cloud formed
 a.    near the present orbits of the terrestrial planets.
 b.    near the present orbits of the Jovian planets.
 c.    at high temperatures.
 d.    from silicate materials.
 e.    outside of the original solar nebula.

69.   The density of Comet Halley was found to be about 0.2 g/cm3. This implies that Comet Halley
 a.    is composed of about 50% rock and 50% frozen water and methane.
 b.    is loosely packed ices with a small amount of rocky material.
 c.    formed in the inner solar system and was ejected by Jupiter to the Kuiper belt.
 d.    is really an S-type asteroid.
 e.    was once a moon of Neptune and was ripped away by a large impact.

70.   Carbonaceous chondrites

 I.       contain mostly iron and nickel
 II.      contain volatiles
 III.       contain chondrules
 IV.       are similar in composition to the S-type asteroids

 a.    II & III
 b.    I, II, & III
 c.    II, III, & IV
 d.    I, III, & IV
 e.    I, II, III, & IV

 71.   What evidence exists that some of the asteroids were geologically active?
 a.    A few of the larger asteroids show small volcanic mountains.
 b.    The moons of Mars, which are thought to be captured asteroids, show evidence of
    flooding by lava.
 c.    The meteorites that are breccias could only have formed in a molten mantle.
 d.    Spectroscopically, Vesta appears to have regions of small lava flows.
 e.    Io is very geologically active with sulfur volcanoes.

72.   The __________ is a disk-shaped cloud of icy bodies believed to extend from about 40 AU out to 100 AU. It is believed that short period comets originate from this region.
 a.    Oort cloud
 b.    WidmanstStten cloud
 c.    Apollo-Amor
 d.    Kirkwood region
 e.    Kuiper belt

73.   The diagram below shows the relative size of Earth's moon and the asteroid 10 Hygiea. Based on this diagram, what is the diameter of 10 Hygiea?

  a.   460 km
 b.    46 km
 c.    4600 m
 d.    46 m
 e.    4600 km


74.   Currently the most accepted explanation of the Tunguska Event is the explosion of
 a.    a German U-2 rocket.
 b.    an iron meteor just above the surface of Earth.
 c.    a stony asteroid just above the surface of Earth.
 d.    a mini black hole in Earth's atmosphere.
 e.    an alien space craft as it crashed to Earth.

75.   The type I, or gas, tail of a comet
 a.    is smooth and featureless with a spectrum identical to that of the sun.
 b.    is present even when the comet is located in the region of the Kuiper belt.
 c.    is unaffected by the magnetic field of the sun.
 d.    always points toward the sun.
 e.    is streaked and shows emission lines of ionized atoms.

76.   The diagram below is a plot of an asteroid's reflected brightness versus it ultraviolet minus visual color (U - V color). In this diagram, which of the asteroids is most likely an S-type asteroid?

 a.    Object 1
 b.    Object 2
 c.    Object 3
 d.    Object 4
 e.    Object 5

77.   __________ are round bits of glass found in some stony meteorites.
 a.    chondrites
 b.    anthrosites
 c.    achondrites
 d.    WidmanstStten patterns
 e.    chondrules

78.   The asteroid Ida has an irregular surface and has a small moon that orbits it. What does this tell us about Ida?
 a.    Ida is geologically active.
 b.    Ida has been fragmented.
 c.    Ida is differentiated.
 d.    Ida is an M-type asteroid.
 e.    Ida is most likely an object that used to orbit Jupiter, but was pulled out of orbit by a


79.   If a large comet struck the Earth,

 I.       large amount of molten rock would rain down on Earth and cause massive forest
 II.       the polar ice caps would melt.
 III.       large amounts of radioactive material would cause the deaths of most animal life
       on the planet.
 IV.       thick clouds of carbon dioxide would form and block out the sun for an
       extended period.

 a.    I & IV
 b.    II & III
 c.    I, II, & III
 d.    I, II, & IV
 e.    II, III, & IV

 80.   An asteroid has an orbital period around the sun of 5.2 years. How far from the sun is this asteroid?
 a.  5.2 AU
 b.    10.4 AU
 c.    27.0 AU
 d.    3.0 AU
 e.    2.3 AU


Complete each sentence or statement.

81.   The __________  planets have larger radii than the __________  planets.

 82.   The adding of material an atom at a time is the process of __________ .

 83.   The diagram below shows the radioactive decay of cesium (135Cs). What is the half-life of 135Cs?

84.   A(n) __________ theory of the formation of the solar system uses sudden events that drastically alter the form of the early solar system.

85.   The dirty snowball model is used as a model for the physical structure of __________.

86.   The largest satellites of Jupiter are known as the __________  satellites.
87.   Volcanism is apparent on many objects in the solar system. However, volcanic activity is known to be currently occurring only on Earth and __________ .

 88.   The one object in the solar system besides Earth suspected of currently having a liquid on its surface is
__________ .

89.   The region of Jupiter that is responsible for the magnetic field is composed of __________ .
90.   The rings of __________  were discovered when they occulted a star.
91.   __________  is the smallest of the large moons of Uranus and its surface has features called ovoids. These ovoids
may have been formed by the upheaval of material by convection in the interior.

92.   The __________ -type asteroids are generally found in the outer portion of the asteroid belt and are very dark.

93.   A(n) __________ occurs when a bit of material enters Earth's atmosphere and becomes incandescent due to friction with the atmosphere.

94.   WidmanstStten patterns are found in __________ meteorites.
95.   Long period comets are believed to originate in the __________ .

96.   A __________  is produced when Earth passes through the debris left by a comet as it passed through the inner solar system.

Indicate whether the sentence or statement is true or false.

 97.   The oldest objects found so far in our solar system are Earth rocks that are 3.9 billion years old.

 98.   The Jovian planets have lower average densities than the terrestrial planets.

 99.   The original cloud from which the sun and planets formed had a composition rich in hydrogen and helium.

 100.   The present motions of the planets were inherited from the rotation of the solar nebula.
 101.   The condensation sequence cannot explain the composition of the terrestrial and Jovian planets.

 102.   When particles in the solar nebula grew large enough, they stopped growing by accretion and began growing by condensation.

 103.   Observations in the infrared have detected dusty nebulae around T Tauri stars.

 104.   Outgassing refers to the formation of an atmosphere by the attraction of gases from the surrounding nebula.

 105.   The pressure of sunlight was one of the forces that cleared the solar nebula.

 106.   Jupiter radiates less heat than it absorbs from the sun.

 107.   Jupiter's interior is mostly liquid helium.

 108.   Both Jupiter and Saturn contain liquid metallic hydrogen.

 109.   Jupiter's ring is composed of particles about the size of tennis balls.

 110.   Saturn's belts and zones are obscured by haze high in its atmosphere.

 111.   Saturn's rings are composed of icy particles.

 112.   Shepherd satellites keep the F ring narrow.

 113.   Satellites that lack craters are generally old, inactive bodies.
 114.   For an observer on Uranus, the ecliptic passes only a few degrees from the celestial poles.
 115.   The rings around Uranus and Neptune are confined by shepherd satellites.

 116.   If Uranus had no moon, it would probably not have rings.

 117.   The rings of Uranus were discovered by the Voyager 2 spacecraft.
 118.   The meteors in meteor showers are believed to be the debris left behind in comet orbits.

 119.   Carbonaceous chondrites have been heated to high temperature at least once since they formed.

 120.   Achondrites are rich in volatiles.

 121.   Jupiter was probably influential in preventing the formation of a planet at the present location of the asteroid belt.
 122.   Some asteroids show evidence of surface activity such as lava flows.

   123.   The type II tail of a comet always points toward the sun.

 124.   The dirty snowball theory suggests that the head of a comet is composed of ices.

 125.   The Kuiper Belt is predicted to be the place where most of the short period comets formed.
 126.   The existence of the Oort cloud cannot be confirmed observationally from Earth because the objects are too small.

Our Solar System
Answer Section


               1.   ANS:   D

               2.   ANS:   A                     OBJ:    TYPE: Web Quiz

               3.   ANS:   C

               4.   ANS:   B

               5.   ANS:   D                     OBJ:    TYPE: Web Quiz

               6.   ANS:   A

               7.   ANS:   B                     OBJ:    TYPE: Web Quiz

               8.   ANS:   D

               9.   ANS:   C

             10.   ANS:   C

             11.   ANS:   D

             12.   ANS:   A                     OBJ:    TYPE: Web Quiz

             13.   ANS:   B

             14.   ANS:   A

             15.   ANS:   A

             16.   ANS:   D                     OBJ:    TYPE: Web Quiz

             17.   ANS:   D                     OBJ:    TYPE: Web Quiz

             18.   ANS:   E

             19.   ANS:   B

             20.   ANS:   E

             21.   ANS:   A                     OBJ:    TYPE: Web Quiz

             22.   ANS:   B

             23.   ANS:   C

             24.   ANS:   E

             25.   ANS:   C                     OBJ:    TYPE: Web Quiz

             26.   ANS:   E

             27.   ANS:   C

             28.   ANS:   C

             29.   ANS:   C                     OBJ:    TYPE: Web Quiz

             30.   ANS:   C

             31.   ANS:   D

             32.   ANS:   E

             33.   ANS:   A

             34.   ANS:   E

             35.   ANS:   B

             36.   ANS:   D

             37.   ANS:   A                     OBJ:    TYPE: Web Quiz

             38.   ANS:   E

             39.   ANS:   B

             40.   ANS:   C

             41.   ANS:   D                     OBJ:    TYPE: Web Quiz

             42.   ANS:   D

             43.   ANS:   D                     OBJ:    TYPE: Web Quiz

             44.   ANS:   A

             45.   ANS:   C

             46.   ANS:   A

             47.   ANS:   A

             48.   ANS:   E

             49.   ANS:   B

             50.   ANS:   E

             51.   ANS:   A                     OBJ:    TYPE: Web Quiz

             52.   ANS:   B

             53.   ANS:   B

             54.   ANS:   D

             55.   ANS:   D                     OBJ:    TYPE: Web Quiz

             56.   ANS:   B                     OBJ:    TYPE: Web Quiz

             57.   ANS:   E

             58.   ANS:   B                     OBJ:    TYPE: Web Quiz

             59.   ANS:   C

             60.   ANS:   B

             61.   ANS:   D                     OBJ:    TYPE: Web Quiz

             62.   ANS:   E                     OBJ:    TYPE: Web Quiz

             63.   ANS:   C

             64.   ANS:   A

             65.   ANS:   A

             66.   ANS:   D

             67.   ANS:   C

             68.   ANS:   B

             69.   ANS:   B                     OBJ:    TYPE: Web Quiz

             70.   ANS:   A

             71.   ANS:   D

             72.   ANS:   E

             73.   ANS:   A

             74.   ANS:   C

             75.   ANS:   E                     OBJ:    TYPE: Web Quiz

             76.   ANS:   C

             77.   ANS:   E

             78.   ANS:   B                     OBJ:    TYPE: Web Quiz

             79.   ANS:   A

             80.   ANS:   D                     OBJ:    TYPE: Web Quiz


             81.   ANS:   Jovian; terrestrial

             82.   ANS:   condensation

             83.   ANS:   3 million years

             84.   ANS:   catastrophic

             85.   ANS:   comets

             86.   ANS:   Galilean

             87.   ANS:   Io

             88.   ANS:   Titan

             89.   ANS:   liquid metallic hydrogen

             90.   ANS:   Uranus

             91.   ANS:   Miranda

             92.   ANS:   C

             93.   ANS:   meteor

             94.   ANS:   iron

             95.   ANS:   Oort cloud

             96.   ANS:   meteor shower


             97.   ANS:   F

             98.   ANS:   T

             99.   ANS:   T

           100.   ANS:   T

           101.   ANS:   F

           102.   ANS:   F

           103.   ANS:   T

           104.   ANS:   F

           105.   ANS:   T

           106.   ANS:   F

           107.   ANS:   F

           108.   ANS:   T

           109.   ANS:   F

           110.   ANS:   T

           111.   ANS:   F

           112.   ANS:   T

           113.   ANS:   F

           114.   ANS:   T

           115.   ANS:   T

           116.   ANS:   T

           117.   ANS:   F

           118.   ANS:   T

           119.   ANS:   F

           120.   ANS:   F

           121.   ANS:   T

           122.   ANS:   T

           123.   ANS:   F

           124.   ANS:   T

           125.   ANS:   T

           126.   ANS:   T