Chapter 9 (The Earth’s Moon)

Module 1 (Overview of the Moon):

What extraterrestrial objects have been directly explored by humans? How do the mass and size of the Moon compare with Earth? Describe the Moon’s orbit. Define “lunar highlands” and “maria.” How are visual appearances of the near and far sides of the moon different? How is the crust different on the two sides of the moon? Does the Moon have an atmosphere? Name four factors that govern whether a moon or planet has an atmosphere, and briefly explain why each factor has an effect. What is the most common type of rock on the Moon? What is the most common type on Earth? Name and describe the most common rocks in the maria and lunar highlands. Could there be water on the moon? If so, where and in what form? How do the density and color of rocks in the maria and highlands compare, and why? In comparison with Earth rocks, are Moon rocks (a) extremely similar, (b) completely different, or (c) somewhat similar but with nontrivial differences?

Module 2 (Tidal Coupling):

What is a “differential force”? Consider a simple model of the Earth in which it is covered completely by an ocean. Describe how and why differential gravitational forces exerted by the Moon deform this ocean. Explain “spring tides” and “neap tides”. What is “tidal locking”? Explain what the “Roche limit” is and give an example in the Solar System where it comes into play. Explain why tidal effects are causing the Earth’s rotation to slow down, why the Moon’s orbit to increase in size and become more circular, and why tidal forces cause heating (these processes are detailed in an animation).

Module 3 (Lunar History):

How old is the moon? Why did the moon’s surface melt? When did this melting phase begin and end? Explain how craters are formed by meteor impacts, and why a crater can be much larger than the meteor itself. What does the amount of cratering indicate about the age of a surface? What does the amount of cratering indicate about the age of the maria and highlands on the Moon, and about the surface of the Earth? What caused the Moon’s period of volcanism? What did the volcanism have to do with the maria? How and why was the volcanism different on the near and far sides of the moon? When did the volcanism start and end? What has been going on geologically on the moon since then?

Module 4 (Formation of the Moon):

Name and describe four hypotheses for the origin of the Moon. Which of these hypotheses holds up best in the face of currently available data, and why?

Chapter 10 (Mercury and Venus)

Module 1 (The Planet Mercury):

How do the size, orbital eccentricity, and orbital inclination of Mercury compare with those of the other planets? How does its rotational period compare with its orbital period? Briefly describe three types of surface features on Mercury. Is there evidence for large-scale tectonic motion on Mercury? Why might this be (i.e. the presence or absence of tectonic motion)? What fraction of Mercury’s volume is occupied by its iron core? How does this compare with the fraction of Earth’s volume occupied by its iron core?

Does Mercury have an atmosphere? Describe the temperature variations on Mercury; how does the variation rank in the Solar System? How does Mercury’s magnetic field compare with Earth’s? Why might it have such a different magnitude?

Module 2 (The Planet Venus):

Name two unusual things about the rotation of Venus. How many moons does Venus have? Which other planets have this same number of moons? Can the surface of Venus ever be seen in visible light? Why? How has information about the surface of Venus been obtained? How many “continents” are then on Venus? Why are they called “continents” even though there is no surface water? How active is the volcanism on Venus in comparison with other objects in the Solar System? Why are there relatively few craters on Venus? Why are there especially few small craters on Venus? Are there several crustal plates moving horizontally relative to each other (plate tectonics), as on Earth? Does Venus have a magnetic field? Why are these last two things surprising? If not by plate tectonics, by what mechanism could the surface of Venus be so young? Why is there a “tail” streaming away from Venus? What is Venus’ atmosphere mostly composed of? What are the clouds composed of? How do the pressure and temperature of Venus’ atmosphere compare with Earth’s? What process has led to these conditions? Describe what “greenhouse gases” do. Describe two “positive feedback loops” that can result in a “runaway” greenhouse effect.

Chapter 11 (The Planet Mars)

Module 1 (Overview of Mars):

What color is Mars? How does its rotational period compare with Earth’s? How does its density compare with that of the other inner planets? What are the polar caps made of? Why do they change with time? Tell how the northern and southern hemispheres of Mars are different. What is the name of the largest volcano on Mars? How does the size and distribution of volcanoes on Mars compare with those on Earth? Explain the difference. How does the thickness of Mars’ crust compare with Earth’s? What evidence is there for the thickness of Mars’ crust? Does Mars exhibit plate tectonics? What two mechanisms have caused erosion on the surface of Mars? How do the sizes of Mars’ core and magnetic field compare with Earth’s? What is the dominant constituent of Mars’ atmosphere? How does the pressure compare with Earth’s atmosphere? What are typical temperature variations? What causes seasons on Mars? What phenomenon does seasonal heating induce? How does the size of Mars’ magnetic field affect its atmosphere? How was evidence for life on Mars searched for in the 1970’s? How many experiments were done, and how many gave positive results? What was the bottom line of these experiments? Compare the history of water and carbon dioxide on Venus, Earth, and Mars.

Module 2 (The Martian Moons):

How many moons does Mars have? What are their names? They are called (fill-in-the-blank) satellites. How do these objects compare with other satellites, such as Earth’s Moon? What is the probable origin of Mars’ moons? What is unusual about the orbit of Mars’ inner moon (as viewed from the surface of Mars)? Explain this behavior. What is the expected ultimate fate of this inner moon? Is capturing an asteroid a commonplace occurrence, or does it require special conditions?

Chapter 12 (Jupiter and the Galilean Moons)

Module 1 (Overview of Jupiter):

How does the mass of Jupiter compare with that of the other planets? How would Jupiter be different if it were about 100 times more massive? Which planets are called the gas giants? Why do they have this name? How does Jupiter’s density compare with Earth’s density? What elements is Jupiter mostly composed of? Name three layers in the interior of Jupiter. What is the likely origin of Jupiter’s inner source of heat? Define “zones” and “belts,” and describe ways in which they are different (altitude, color, pressure, temperature, wind direction). Describe the differences in weather between Jupiter and Earth. How large is the Great Red Spot? How long has it persisted? Name two factors that have allowed the gas giants to retain large amounts of hydrogen and helium.

Module 2 (The Magnetosphere):

Define “magnetosphere.” How strong is Jupiter’s magnetic field and how large is its magnetosphere (both in comparison with Earth)? Name two reasons why its magnetosphere is so large. What is the origin of Jupiter’s magnetic field? Describe the “plasma torus” and “flux tube.” Which of Jupiter’s moons is associated with these structures? What is the source of the charged particles in these structures? Is this the same source of charged particles trapped in Earth’s magnetic field? What do the positions of the aurorae tell us about the alignment of Jupiters rotation axis and magnetic field axis?

Module 3 (The Galilean Moons):

How many moons does Jupiter have? Where does the term “Galilean moons” come from? Name the “Galilean moons”; where do the names of these moons come from? How does the geologic activity of Io compare with other bodies in the Solar System? Io is covered with what geologic feature? What is the source of Io’s volcanic activity? Is it the same as the source of Earth’s volcanic activity? In comparison with Earth, how often is Io “resurfaced”? Why is Io not tidally locked? Describe the surface of Europa. What may lie under Europa’s frozen surface? How does the size of Ganymede compare with other bodies in the Solar System? What covers its surface? In what ways is the structure of Ganymede similar to Earth? How is the surface of Callisto similar to and different from the surfaces of Europa and Ganymede? Characterize the level of geologic activity on Callisto and the age of its surface; what is the evidence for this? Compare and constrast the structure of the Galilean moons.

Module 4 (Other Satellites of Jupiter):

What is a possible origin of the smaller moons of Jupiter? How was the ring of Jupiter discovered? What is its position relative to Jupiter’s moons? How do the brightness and composition of Jupiter’s ring compare with these properties of Saturn’s rings? What are possible sources of the particles in Jupiter’s ring? What may act to stabilize the ring?

Chapter 13 (The Planet Saturn)

Module 1 (Overview of Saturn):

What was the most distant planet known to the ancients? Among the planets, how does Saturn rank in mass, size, and density? Why is Saturn “oblate” (flattened), rather than spherical? What two elements make up most of Saturn? “Saturn, like Jupiter, has no (fill in the blank). What we perceive as a (fill in the blank) is actually the tops of the clouds. Also like Jupiter, the highest clouds seen in Saturn’s atmosphere appear to be crystals of frozen (fill in the blank).” Like Jupiter, Saturn has a banded appearance, but what is different about the color contrast? Why might this be? Name four probable layers in the interior of Saturn. Like Jupiter, Saturn emits more energy than it receives from the Sun; what are the two likely sources of this internal heat? Why does Saturn have both these sources, while Jupiter has only one of these heat sources? While both Saturn and Jupiter have high wind speeds, what is a difference between Saturn and Jupiter with regard to variations in wind speeds? How does the magnitude of Saturn’s magnetic field compare with that of Jupiter (and Earth)? What is the source of Saturn’s magnetic field? How closely aligned are the rotation axis and magnetic field axis of Saturn, and how does this compare with some other planets? Where did Jupiter and Saturn get their hydrogen and helium? Why don’t the terrestrial planets have large amounts of these gases?

Module 2 (The Ring System):

Are the rings of Saturn solid? Why or why not? Name the seven major rings of Saturn from outside in. What does the lettering denote? Which rings are visible from Earth? How were the others discovered? How can the nature of the particles composing the rings be inferred? Describe the size and composition of the particles making up the rings. How do they differ from the particles making up the ring of Jupiter? Give an indication of how much mass is in the rings, and how thick the rings are. Name the two largest gaps in the rings and tell where they are. Roughly how many gaps are there? Aside from faint rings that inhabit some of the apparent gaps, what objects are there in some of the gaps? What do “sheperd moons” have to do with the rings?

Module 3 (The Moons of Saturn):

How many moons does Saturn have? Describe three groups these moons fall into. Why is the atmosphere of Titan opaque? What is the primary constituent of this atmosphere? What sort of lakes or oceans may be on the surface of Titan? Describe in a general way the surfaces of Saturn’s other moons. What are they probably composed of?

Chapter 14 (The Outer Planets)

Module 1 (The Planet Uranus):

When and how was Uranus discovered as a planet? Among the planets, where does Uranus rank in mass and size? What is unusual about its rotation? What color is it, and what causes this color? Why is this color different from Jupiter and Saturn? Name three layers of the interior of Uranus (according to our best understanding). Does it have an internal heat source? As one moves out from Jupiter to Neptune, what happens to the amounts of ammonia and methane the atmospheres of these planets? What is surprising about the wind flow patterns of Uranus and Neptune? How strong is Uranus’ magnetic field compared to Earth’s? Name two unusual things about its magnetic field. What other planet shares these two unusual features in its magnetic field? What is a possible origin of the magnetic field in these two planets?

Module 2 (Satellites of Uranus):

How many moons does Uranus have? Describe two groups they fall into. How were the rings around Uranus discovered? How many rings are there?

Module 3 (The Planet Neptune):

When and how was Neptune discovered? Which planet is Neptune most similar to? Among the planets, where does Neptune rank in mass and size? How do its surface features compare with those of Uranus? Name three layers of the interior of Neptune (according to our best understanding). What is the likely origin of its internal heat source? How does the color of Neptune compare with Uranus? Why? What is the probable cause of the greater activity in the atmosphere of Neptune than that of Uranus? What are the large dark spots on the surface of Neptune? How does their stability compare with the Great Red Spot of Jupiter? How does Neptune’s magnetic field compare with that of Uranus?

Module 4 (Satellites of Neptune):

How many moons does Neptune have? Describe two groups they fall into. What is unusual about the orbits of the larger moons? What unusual feature adorns the surface of Triton, Neptune’s largest moon? How were Neptune’s rings detected? How many have been identified?

Module 5 (Pluto and Charon):

When was Pluto discovered? Among the planets, where does Pluto rank in mass and size? Name some unusual aspects of Pluto’s orbit and rotation. Is it always further from the Sun than Neptune? What is the only planet to which an Earth-launched spacecraft has not traveled? How was the surface of Pluto imaged (resolved) for the first time? How is it known that Pluto has an atmosphere? When was Pluto’s moon discovered? What is its name? Describe the tilt of Charon’s orbit. What is an interesting consequence of the fact that Pluto and Charon have masses that are not all that different? (Hint: What does it do to orbits of these bodies?) Describe the composition of Pluto and Charon.

Chapter 15 (Comets)

Module 1 (Overview of Comets):

Comets appear to be composed of (fill in the blank), (fill in the blank), (fill in the blank), and (fill in the blank) ices, with (fill in the blank) mixed in. What does this composition represent a sample of? Roughly how often does a comet easily visible to the naked eye appear? Unlike other bodies in the solar system---which are influenced only by gravity---what other force affects the motion of comets? With regard to how often they appear, what is the difference between comets on elliptical and parabolic orbits? Describe the typical orbit of a short-period comet; roughly how many of these pass through the inner solar system each year? What source probably replenishes the supply of short period comets? What is the extent of this region? Which planet might be closely associated with this region? The long-period comets, primarily responsible for bright comets visible to the naked eye, come from what region? Describe the nature, size, and total amount of material in this region. Describe the “nucleus” and “coma” of a comet. How large can the tails of comets be? Name and describe two kinds of tails that a comet can have.

Module 2 (Some Important Comets):

Who used Newton’s recently developed theory of gravitation to predict the return of a comet in 1758? In addition to its basic elliptical orbit around the sun, what else did he have to account for in making this precise prediction? Roughly how often does this comet return? Name two bright comets that appeared in the 1990s. Describe two occasions in which comets collided with planets.

Chapter 16 (Asteroids and Meteors)

Module 1 (Overview of Asteroids):

What are asteroids? What is their range of sizes? Where is the highest concentration of asteroids? Name three groups of asteroids not confined to the asteroid belt, and describe their locations/orbits. Characterize the estimated total mass of all asteroids put together. What are Kirkwood gaps? Describe the resonance interaction that gives rise to them. What is the probable reason the asteroids never coalesced into a planet? Roughly how many asteroids are known to cross Earth’s orbit?

Module 2 (Meteors):

Define “meteoroids” and “meteors.” What causes the visible trail left by a meteor? How often do meteors typically occur? Times of much higher rates of meteor occurrence are called (fill in two blanks). What causes these events? During such times of higher rates of meteor occurrence, the meteors appear to come from a particular point in the sky, called the (fill in the blank). How are these events named? What are “fireballs” and “bolides”?

Module 3 (Meteorites):

How much total mass in meteoroids enter Earth’s atmosphere each day? Characterize the most common size of these, and their usual fate. What is a “meteorite”? Most meteors come from (fill in the blank). Most meteorites come from (fill in the blank); why? Name and describe three classes of meteorites. Why are meteorites important scientifically? Describe three aspects of the explanation of why rocks of different composition fall out of our sky. Aside from asteroids and comets, what two other bodies in the solar system have been the source of meteorites? How could material from these bodies end up on Earth?

Module 4 (The K-T Event and Impacts):

Roughly how often do meteorite impacts occur that would be capable of killing millions of people if they were to occur in urban areas? Describe what happened in the K-T Event. What are two pieces of evidence indicating that the impact of a large chondritic asteroid caused this event? How often are impacts of this magnitude thought to occur?