Version: February 19, 2019
Test 2: Review Sheet
Test: February 21, 2019
Sample short answer questions and short answer question topics
1. What are the orbital (dynamical) regularities and what are the
regularities of 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? How well do these notions fare in terms of the recent observations
of exgra-Solar planets?
2. Compare and contrast the Terrestrial, the Jovian planets, and the
rocky/icy planets in terms of their
sizes, masses, distances from the Sun, interior chemical compositions,
atmospheric compositions and masses, dnesities.
3. What are dwarf planets (what is the definition of dwarf planets)?
What was the category of dwarf planets created? What are some members of
the class of dwarf planets? What is the Kuiper belt? What is New Horizons
and what discoveries were made by the New Horizons mission? What is
Ultima Thule? What is the significance of Ultima Thule?
4. What is the condensation theory? What is the Solar Nebula?
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 three types of planets in our Solar System? 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
for planetary formation?
What are refractory elements? What are volatile elements?
5. What are planetesimals? What are protoplanets? Describe how they
fit into the scheme for Solar System formation.
What is the current understanding as to why
Jupiter/Saturn and Uranus/Neptune are so different?
6. What are the two primary methods used to detect extra-solar planetary
systems? What is the Doppler Effect? What is an occultation? What is a
transit? Why does the spectroscopic primarily discover Jupiter-like planets?
Why does Kepler typically discover planets with short orbital periods?
7. Roughly how many extra-solar planets are now known?
Roughly how many extra-solar
planetary systems have been discovered? In terms of the properties of the
newly discovered systems, how does our understanding of the formation
mechanisms of planetary systems fare? That is, how do the properites of our
Solar System compare to the newly discovered systems? If there are
discrepancies,
are the discrepancies disqualifying discrepancies or are they perhaps
understandable? Explain how you arrive at your conclusions. What are
hot Jupiters? What are super-earths? What is the most common type of
planet in our galaxy? What are hot Jupiters? What are sub-neptunes?
8. Are Kepler's laws universal? Is there evidence that Kepler's laws are
universal?
9. What are the best current ideas concerning the origin of the asteroids?
10. What are the best current ideas concerning the origin of our Moon? How
does our model for the origin of the Moon shed light on the origin of
the Earth's atmosphere?
What is the evidence that supports the
giant impact theory? what is the giant impact theory?
1. Describe how one uses radioactive age dating to determine the age
of a rock. What is radioactive heating? Why is it significant?
2. 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 late heavy bombardment on the Moon occurred ~3.8-4.2
billion years ago. What is the
period of late heavy bombardment?
What has been proposed as a cause for the late heavy bombardment?
Describe the rate of cratering on the Moon and the Earth over the last
4.5 billion years. Is the number of craters produced per year on the
Earth greater than the number produced on the Moon? Explain your
answer.
3. Briefly describe Plate Tectonics.
What are the signatures of Plate Tectonic activity (describe rift zones,
subduction zones, transform faults)? What drives plate
tectonic activity? What are the lithosphere and the asthenosphere? How do
they differ from the core, mantle, and crust?
4. Roughly, how many plates are on the surface of the Earth?
What drives geology on any planet? What evidence and
facts led Wegener to propose the theory of plate tectonics?
5. Why was the
theory not immeditately accepted? What eventually led to the acceptance
of the theory of plate tectonics?
6. Contrast oceanic plates to continental
plates. What are rift zones, subduction zones? Describe
what occurs at the places where different plates collide and the locations
where different slide along each other.
7. What is the Juan de Fuca plate? Why is the Juan de Fuca plate
of significance to us in Oregon? What geological activity is associated with
the plate interactions in the Plate Tectonic theory? What are shield volcanoes?
What makes the Hawaiian islands a chain of islands? What are plumes? Why don't
the Hawaiian island volcanos fall near plate boundaries?
9. Describe the surface features of the moon.
What are maria? How were they formed? Where are they
found? When were they formed? On what objects are maria found?
10. What is the rate at which large craters (D > 100 km) are formed on
the Earth (the rate at which the purported dinsoaur killer
events occur)?
11. How are the ages of the surface
features on the Moon determined? How are the ages of surface features
on Mercury estimated? How do the ages of the surace features on the Earth,
Venus, Mar, Moon, and Mercury compare? If different, why are they different?
12. What are the ways in which energy is transported (given in class) for
earth-like planets?
Describe convection?
What is conduction? What is radiation transport? Near a campfire, explain
why you feel heated if you are above the flames, on the ground away from
the flames, and why your hand feels warm if you hold an iron poker placed
into the fire. Which dominates in the asthenosphere of the Earth?
13. How does radar ranging work (on Venus by Magellan)?
What information can be obtained from
radar ranging? What is its significance for Venus and why was it used on
Venus? What is
Magellan?
7. If all of the water on the Earth were in liquid form and spread over the
Earth, to what depth would the Earth be covered? If the same was done on Venus,
to what depth would Venus be covered?
1. Describe the interior strctures of the Terrestrial planets. What is
chemical differentiation? What are accretional heating and radioacrive heating?
When does chemical differentiation occur?
2. How does the desnity of a planet give clues as to its internal chemical
make-up?
3. What determines the size of the atmospheric pressure on an earth-like
plaent? Contrast the earth-lke planets in terms of their atmospheric pressures,
atmospheric compositions, and atmospheric masses.
4. In terms of geology, how are big and little planets defined?
What are the big earth-like planets? What are the small earth-like planets?
What determines the rate at which an earth-like planets cool? Explain how this
woks. Do these ideas hold for all other bodies in the Solar System?
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
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
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!
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.
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
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
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
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
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
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
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
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.
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
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 15. The Greeks supported the notion that the Earth was stationary in the center of the Celestial Sphere by
a. simply stating, "that's the way it is, Bud." b. showing that the stars were much smaller than the Earth. c. their failure to detect daily changes in star positions. d. their failure to find other life in the Solar System. * e. their failure to detect annual shifts in star positions. 32. The assumption that the stars are fixed firmly to the Celestial Sphre turns out to be reasonable because
a. stars are, in fact, stationary; they do not move b. stars move very slowly compared to planets; speeds much less than 1mile per hour * c. stars are extremely distant d. stars are fairly nearby e. stars are optical illusions
34. Which of the following is true about the motions of the planets?
a. They, in general, move west to east through the stars. b. They move through the Zodiac constellations. c. They rise in the east and set in the west over the course of a day. d. At times, they perform loops on the sky known as Retrograde motion. * e. All of the above statements about planets are true.
37. Precession
a. is the accuracy with which numbers are given in astronomy * b. causes the motion of the Earth's rotation axis on the Celestial Sphere c. produces the apparent backward motion of the planets on the sky d. causes the daily eastward motion of the Sun on the Celestial Sphere