Test 2: Review Sheet
First review your class notes, then review the web notes, and, lastly, read the suggested pages in the text.
Current Exam: Version 1, Version 2, Version 3.
VERSION: February 19, 2010 @ 5:13 pm:
VERSION: February 25, 2010 @ 5:27 am: Topcis 4, 4a, 4b, and Topics 5, 5a, 5b will be included on the exam.
Old Exam. Be sure to look at the old exam from review sheet 1 to pick out the general Solar System materials. Also note that the amount of material and the depth to which certain topics are covered varies from year-to-year.
Short Answer Questions to prod you a little. Discussions of the posted issues can be found in your class notes, web notes, and the homework assignments.
1. More than 400 extra-Solar planets have been discovered in the last 15
years. Roughly how many other planeary sysmtes have been found? What method
was used to discover most of these planets? What other methods are used?
What is the Doppler shift? What is Kepler and what important
results will Kepler potentially produce? What is
gravitational microlensing?
2. How do the new planetary systems compare to our Solar System in terms
of the planets eccentricities, inclinations, and Jovian/Terrestrial planets?
What is the simplest way in which to differentiate between Jovian and
Terrestrial planets in this sample? What do they
tell us about how our Solar System formed?
3. What is the center of mass of a system? Why is it an important concept
for planet searchers?
4. What the dynamical regularities and what are the planetary properties
any viable theory for the origin of our Solar System must explain? What are
some minor dynamical regularities any theory for the Solar System must
explain?
5. Compare and contrast the Terrestrial and Jovian planets in terms of their
sizes, masses, distances from the Sun, chemical compositions, atmospheres,
magnetic fields, densities.
6. How does the condensation theory for the
origin of the Solar System account for the dynamical regularities of the
Solar System and for the
fact that there are two main types of planets in our Solar System? How do the
dwarf planets fit into this picture. why are
the Jovian planets so much more massive than the Terrestrial planets?
What is the Snow Line? What is the significance of the Snow Lines?
What are refractory elements? What are volatile elements?
7. What are planetesimals? What are protoplanets? Describe how they
fit into the scheme for Solar System formation.
8. What is meant by accretional heating? Radioactive heating? What are
the primary nuclei that heat the Earth? Why are these important for
the chemical differentiation? (What is chemical differentiation?)
9. Describe how one uses radioactive age dating to determine the age
of a rock. What are some important elements used for radioactive age
dating? Explain how you could judge the age of rock.
10. The layers of the Earth defined by their chemical
composition are ____ .
11. The layers of the Earth defined by their
mechanical properties are ____ . How are these layers differentiated (that is,
what mechanical properties are used to define these layers?)
12. List the ways astronomers probe the interiors of the
Terrestrial planets. What
has been the most useful method for the Earth?
What has been the best method for Mercury? What are P waves? What are S waves?
What are the Shadow Zones? Which type of wave travels the fastest
through the Earth? Compare the interiors of the Earth and the Moon.
13. Describe the surface features on the Moon. What are the oldest
regions? What are the youngest regions? How are the relative ages
of the various features determined? How are their absolute ages determined?
The period of heavy bombardment on the Moon occurred ~4
billion years ago. What is the
period of the heavy bombardment?
What was proposed as a cause for the period of heavy
bombardment? What are maria? How were maria formed? How old are maria? Are
the maria spread uniformly on the surface of the Moon? How were the Lunar
mountains formed? How has the rate of cratering on the Moon changed with
time?
14. What are seismic waves? What are S waves? What are P waves?
What is the Shadow Zone?
15. Explain why large planets like the
Earth and Venus have active geologies while small planets like the
Moon and Mercury are geologically dead.
16. What are the two primary
suggestions for the origin of the secondary atmospheres of Venus and
Earth? Why don't the Moon and Mercury have atmospheres?
17. What are the primary effects that need
to be considered when trying to determine
whether a planet can or cannot hold onto to an atmosphere?
18. Today, Venus has a massive
atmosphere of CO2 while the Earth has an atmosphere of
Nitrogen and Oxygen with little CO2.
What happened to the CO2 that presumably
was once in the Earth's atmosphere? Where is the CO2?
19. Venus and Earth are essentially twin planets in their general properties.
What caused the atmosphere's of the two planets to evolve so differently?
20. Earth and Mars are very similar planets in terms
of their general properties. What caused the
atmospheres of the two planets to evolve so differently?
21. What are the signatures of Plate Tectonic activity? What drives plate
tectonic activity? What drives geology on any planet? What is convection?
Why does convection arise? Who is Alfered Wegener? What evidence
supports Plate Tectonics? What are rift zones? WHat are subduction zones?
What are transform faults? What is Juan de Fuca plate? Why is it important
to us here in Oregon? What are shield volcanoes? What are the largest shield
volcanoes found on the Earth? How do shield volcanoes differ from
cinder cone volcanoes? Where are the largest shield volcanoes in the
Solar System found?
Roughly, how fast do the continents drift apart?
Roughly, how long does it take for oceanic crust to be recycled?
22. Describe the surface features of Mars. What is Valles Marineris? What is
the Tharsis Bulge? Is there evidence for flowing water on Mars?
Is there evidence
that water once flowed on Mars? If so, what is the evidence for either event?
Do we believe that Plate Tectonic activity occured
on Mars? Cite a piece of evidence which supports
your answer. What about Venus?
23. Describe the surface features on Venus. What are rolling plains, highland
regions, and lowlands on Venus? What are Ishtar Terra, Beta Regio,
and Aphrodite Terra? Are there active volcanoes on Venus? Are there volcanoes
on Venus? Venus is enveloped by a dense cloud layer; how has the surface of
Venus been mapped? Describe the Magellan mission. Does Venus show signs
of Plate Tectonics? Cite evidence to support your views.
Venus is very dry compared to the Earth. Where is Venus's water?
What happened to Venus's water?
24. What is the Gaia Hypothesis?
According to the Gaia Hypothesis as described in class,
how would the Earth react
if the energy output of the Sun were to increase?
25. What are maria? How were they formed? Where are they
found in the Solar System?
26. In what level of the atmosphere do we
find the ozone layer? What important services does the
ozone layer provide for us?
27. How are the ages of the surface
features of Mercury estimated?
28. Which planerts have the youngest surface features? Which planets
have the oldest surface features? If all planets formed around 4.6
billion years when the Solar System formed, what does it mean to say some
planets have younger or older surfaces than other planets?
29. What is a strong piece of evidence that the event which produced the
Chicxulub crater led to the demise of the dinosarus at the K-T boundary? In
what ways could a large impact lead to the demise of the dinosaurs? What could
be a problem with the suggestion that a large impact led to the demise of the
dinosaurs?
More Sample Multiple Choice Questions
1. A feature of the Jovian planets is that
a. they are composed primarily of methane and ammonia gas b. they are larger than or around the size of Juptier * c. they are composed primarily of hydrogen d. they have relatively hard surfaces of water ice e. they are all about the mass of Jupiter or larger
2. When we refer to the process of chemical differentiation, we are talking about the process whereby
a. the planets form by first accreting iron and then adding layers of the lighter layers sequentially b. the dust grains and other particles sink to the mid-plane of the Solar Nebula c. the lithosphere rises so that it sits on top of the asthenosphere * d. the heavier (more dense) elements sink to the center of the young Earth e. the Terrestrial planets form closer to the Sun than do the Jovian planets
3. Which of the following facts must any theory for the formation of the Solar System explain?
a. the nearly circular orbits of the planets b. why the Jovian planets are so massive when compared to the Terrestrials c. the nearly co-planar orbits of the planets d. the chemical compositions of the Jovian planets * e. It should be able to explain all of the above facts
4. Of the following planets, which one's orbital characteristics differs the most from the other listed planets?
* a. Mercury b. Earth c. Uranus d. Neptune e. Jupiter
5. Which of the following is a characteristic of the Terrestrial planets?
a. high density b. solid outer layers (hard surfaces) c. small sizes (diameters < diameter of the Earth) d. they are not very far from the Sun (a < 2 A.U.) * e. All of the above are charateristics of the Terrestrial planets.
6. The chemical composition of the atmosphere of Mars is most similar to the atmosphere of
a. Jupiter * b. Venus c. the Earth d. the Moon e. Mercury
7. The plastic region in the interior of the Earth where energy is transported by convective motions is the
a. core b. mantle * c. asthenosphere d. lithosphere e. crust
9. The currently accepted theory for the origin of the Moon
a. proposes that the young Earth spun rapidly and ejected the Moon from its surface b. proposes that the Moon was formed outside of the Solar System and was subsequently captured by the Sun * c. proposes that the young Earth was struck by a Mars-sized object which led to the formation of the Moon d. proposes that Earth and Moon formed independently but from one collapsing gas cloud
10. A key to understanding why there is a large difference between the masses of the Jovian planets and the Terrestrial planets is
a. that water was able to exist in solid form (ice) only near and beyond the orbits of the Jovian planets b. the fact that only in the outer Solar System could forming planets capture and hold hydrogen and helium c. rocky material could only be in solid form beyond the orbits of the Jovian planets * d. only a and b e. a, b, and c
11. We expect the Earth's core to be more dense than its crust because
a. in the early stages of the Earth's formation, its interior was molten (or at least, it was soft) b. the density of material in the crust is less than the overall average density of the Earth c. any material becomes more dense as it is compressed by the weight of the material lying above it * d. all of the above are correct e. only a and b are correct
12. The light-colored regions on the Moon are
a. the highlands and are thought to be the youngest features on the Moon * b. the highlands and are heavily cratered c. the maria and are thought to be old; ages up to 4.6 billion years d. the maria and are thought to be around 3.2 - 3.8 billion years old e. wind-swept plains formed early in the Moon's history
13. The study of the Moon's surface and rocks has revealed that
a. a short period of intense bombardment occured around 1 billion years ago b. the cratering history of the Moon is anomalous in that it is different from what we know about the cratering rates of the other planets * c. the rate of impacts was very high 4 billion years ago but then precipitously to its current levels d. the far side of the Moon has never been struck by objects as large as the ones which struck the near side of the Moon (and formed the maria)
14. The relative ages of the regions on Mars can be inferred from
a. the heights of their volcanos b. the lengths of their canyons (e.g., Valles Marineris) * c. the number of craters d. the sizes of their largest craters e. the number of volcanos they contain
15. Active geology on a planet
a. requires the existence of a lithosphere b. requires an extensive and thick atmosphere c. only occurs when the planet has a sizable moon * d. will only occur if the planet has a hot interior e. will only occur on smaller planets, in general
16. On the Earth, the oceanic plates
a. are less dense than the continental plates * b. are re-cycled roughly every 100 - 200 million years c. contain some of the oldest surface features found on the Earth d. are thought to be composed mainly of iron and nickel e. tend to float on top of the continental plates
17. Continental drift (plate tectonic activity) may be driven by
a. strong winds b. ocean currents c. earthquakes d. volcanism * e. convection
18. The Tharsis region on Mars
a. shows some of the oldest surface features on Mars b. lies for the most part below the sea level on Mars * c. is a region of very recent volcanism d. contains both heavily cratered and relatively uncratered regions e. is strong evidence that, in the past, Mars showed extensive plate tectontic activity
19. The Martian surface shows a striking asymmetry between its northern and southern hemispheres. The differences show up
a. in the composition of the atmosphere above each region * b. in the elevations of the regions c. in the number of continents each contains d. in the amount of plate tectonic activity each exhibits e. All of the above are examples of the striking differences between the two hemispheres
20. Which of the following statements about the surface of Venus is correct?
a. The surface of Venus is thought to be ancient, 4.6 billion years old b. There is an overabundance of craters with diameters less than 30 km on Venus c. Most of the surface of Venus is fairly young, only 3 billion years old d. The surface of Venus is covered primarily by continental-type regions * e. Venus's lithosphere is thought to be weaker and more pliable than the Earth's lithosphere
21. The surface of Mercury is more like that of _____ while its interior is more like that of _____ .
a. the Moon; Jupiter b. Mars; Venus * c. the Moon; the Earth d. Mars; Jupiter e. Mars; the Earth
22. The atmospheric pressure of a planet
a. is a measure of the surface temperature on the planet * b. is a measure of the mass contained in the atmosphere of a planet c. is a measure of the temperature of the gas around the planet d. tells you the composition of the atmosphere of the planet
25. Which of the following is a true statement about an S wave?
a. It is a wave whose disturbance is in a direction parallel to its direction of propagation * b. An example of an S wave is a wave travelling down a rope c. An example of an S wave is a compression wave moving along a spring d. S waves can only be produced by earthquakes. e. S waves can only propagate along the surfaces of planets
26. Compared with the side of the Moon facing the Earth, the lunar backside has
a. more maria b. substantially fewer craters c. substantially fewer mountain ranges * d. a thicker crust e. an active volcano!
27. Which of the following facts must any theory for the formation of the Solar System explain?
a. the orbital properties of the Galilean moons of Jupiter * b. the existence of general classes of planets c. the origin and properties of the Earth's moon d. the origin of the atmospheres of the Terrestrial planets e. Venus rotates in the opposite sense that it revolves about the Sun
28. The Solar System is thought to be
a. 100 - 200 million years old b. 46 million years old * c. 4.6 billion years old d. 10 billion years old e. 300 - 800 million years old
29. Which of the following Terrestrial planets shows strong evidence for past or present plate tectonic activity?
a. Venus * b. Earth c. Mars d. only the Earth and Venus e. Venus, Earth, and Mars
30. The majority of the surface features on Mercury were formed via
a. plate tectonic activity b. erosion c. volcanism * d. impacts e. a few very large impacts due to asteroid-sized objects
31. What explains the lack of small impact craters (less than 1.4 km) on Venus?
a. objects of the size needed to produce such craters never reach the surface of Venus due to Venus's strong magnetic field * b. the thick atmosphere burns up most objects which produce craters of this size c. small impact craters have been eroded by water and wind d. the statement is incorrect -- there are many such small craters on Venus
32. A measurement of the density of a planet can tell us
* a. the rough composition of the planet b. the age of the planet c. the mass of the planet d. the size (diameter) of the planet e. All of the above can be deduced from only the density of a planet.
33. The heat which melted the young Terrestrial planets came primarily from
a. nuclear fusion reactions similar to those that heat the Sun b. the sunlight absorbed from the young Sun c. the decay of radioactive elements * d. the high-energy impacts (accretion) of planetesimals e. the energy produced by the burning of fossil fuels
34. Based on the composition of the Earth, we define the following regions in the interior of the Earth (in order of increasing distance from the center of the Earth)
a. troposphere, mesosphere, stratosphere * b. core, mantle, crust c. mantle, core, crust d. lithosphere, hydropshere, asthenosphere e. core, asthenosphere, lithosphere
35. Near subduction zones, we expect
a. to find large changes in the level of the oceans * b. to find active volcanism c. to see the formation of island chains (like Hawaii) d. to observe the creation of new continental crustal material e. to see sea-floor spreading
36. Due to the continuous creation of crustal material
a. the Earth is growing in diameter by around 2 - 3 cm per year. b. the land masses (continents) are being continuosly destroyed c. the Earth is getting more massive as time goes by * d. the ocean basins are replaced every few hundred million years e. the sea level is rising by around 2 - 4 cm per year
37. The mountains on the Moon are
a. strong evidence for the recent collision of continental plates b. caused by hot-spots in the mantle of the Moon * c. created by the impacts of large objects on the Moon d. evidence of extensive volcanism in the early history of the Moon e. evidence that the Moon was once part of the Earth
38. We know that the Lunar maria formed after the Lunar highlands because
* a. the highlands are more heavily cratered than are the maria b. the maria are at lower elevations than are the highlands c. there is a lack of maria on the far side of the Moon d. the highlands are darker in color than are the maria e. most of the Moon is covered by highland regions
39. Of the following planets, which has the largest iron core relative to its overall mass?
* a. Mercury b. Venus c. Earth d. Moon e. Mars
40. In astrometric searches for other solar systems,
a. we search for transits of planets in front of candidate stars (eclipses) b. we search for small periodic changes in the wavelengths of the radiation from nearby stars c. we search for small periodic changes in the pulsation period of pulsars * d. we search for small periodic changes in the positions of stars e. we search evidence of young forming stars
42. Terrestrial planets start with different chemical compositions than Jovian planets because
a. they formed in parts of the Solar Nebula which had radically different chemical compositions * b. of the high temperatures in the inner solar nebula c. Terrestrial planets are smaller than the Jovian planets d. Jovian planets have stronger magnetic fields e. Jovian have many moons which altered their atmospheres
43. Which of the following processes is likely to have been the most important in the formation of the Earth's atmosphere?
* a. vaporization of impacting comets b. gravitational capture of surrounding gases c. respiration of living organisms * d. outgassing from its interior e. radioactive decay of heavy elements such as uranium
44. The surface of Venus is around
a. 4.6 million years old b. several trillion years old c. 4.6 billion years old * d. 300 - 800 million years old e. 100 - 200 million years old
45. Which of the following statements best describes the formation of the Lunar maria?
a. melting and crust solidification followed by impacts b. massive volcanism and the subsequent cooling of the crust * c. large impacts followed by volcanism d. massive volcanism followed by large impacts e. uplifts and subsequent collapses of the lunar crust
46. Modern data indicates that Venus
a. has extensive, rapid, and current continental drift b. has never had volcanic activity c. is covered mainly by continent-like regions (highlands) * d. may have had recent volcanic activity e. is covered by a layer of water to a depth of roughly 2 -3 kilometers
47. A major reason for the large size of the volcanos on Mars is
* a. the probable lack of continental drift on Mars b. the rapid motion of continental plates on Mars c. the large number of volcanos on Mars d. the small size of Mars
48. Based on the appearances of the Moon, Mercury, and the Earth, plus knowledge of their interiors, we might conclude that
* a. Mercury and the Moon have changed little in the last 3 billion years while the Earth is evolving continuously b. both Mercury and the Earth are still evolving, while the Moon is dead c. All three of the objects are geologically active today d. The surface on all three of the objects may be considered permanent, that is, they are unchanging
49. Large quantities of rock (new crustal material) are emerging from the mantle a. along the tops of continental mountain ranges (such as the Himalayas) b. along the boundaries between continental and oceanic plates c. along the major continental rivers (such as the Mississippi) where the crustal plates are the thinnest * d. along the rifts found between oceanic plates