NAME ________________________________________________________
Test 4
Astronomy 121
July 17, 2014
20 multiple choice questions each worth
1 point. Select the best answer
Multiple Choice Questions, 20 questions--1 point per question.
Select the best answer.
1. Comparative planetology _____ .
a. helps us to understand the physics of the Earth
b. helps us to understand how the Solar System formed
c. helps us to learn which planets are suitable for
life as we know it
d. helps us to understand planetary physics
e. All of the above are true.
5. The conditions in the current atmosphere of Mars are _______ .
a. such that water cannot exist in any form on the surface of
Mars
b. such that one expects a substantial stratosphere to form
c. such that liquid water cannot exist on the surface of Mars
d. such that one expects that life could exist near the
equator on Mars during the summer months
6. When Mars was young, its climate was believed to be similar
to the current climate of the Earth. Its atmosphere then evolved
to what it is today. The current wisdom says
that this was because of _______ .
a. the impact of a large object which caused the
Martian atmosphere to boil-off
b. the lack of large-scale plate tectonics on Mars
c. a stage of intense volcanism, as has also been postulated
for the Moon
d. the rapid cooling of the interior of Mars
e. the depletion of the Martian ozone layer
8. Of the following, which suggests that Mars has a
permafrost layer?
a. Valles Marineris
b. splosh craters
c. seasonal polar ice caps
d. sinuous dried riverbeds
e. the residual northern polar ice cap
9. In the Greenhouse Effect on Earth, carbon dioxide
traps _____ in the atmosphere.
a. x-rays
b. ultra-violet radiation
c. infrared radiation
d. visible light
e. microwaves
12. The Greenhouse Effect _____ .
a. explains why Venus's surface temperature is 800-900 F
b. explains why the Earth has an average temperature of 70 F and not -4 F
c. helps us to understand why the Earth was warmer in the past when the
Sun was less bright
d. only a & b are true
e. a, b, & c are all true
13. The current atmospheres of the Terrestrial planets are _______ .
a. the result of volcanic outgassing
b. the result of the capture of many comets
c. gases captured directly from the cloud that formed the Solar
System
d. A combination of a & b
e. The combination of a, b, & c
14. The majority of the Moon's surface is best described as _______ .
a. rolling plains
b. highland regions
c. lowlands
d. maria
e. lava plains and shield volcanos
15. Continental plates on the Earth _______.
a. are much younger than oceanic plates
b. make up the plastic portion of the lithosphere
c. are less dense than oceanic plates
d. flow easily because they are molten iron
e. are found only near the poles of the Earth
16. The Tharsis region on Mars _______ .
a. is a large impact basin that lies, for the most part,
below sea level on Mars
b. is the oldest region on Mars
c. was formed by a large impact, similar to the one that formed our Moon
d. contains both heavily cratered and relatively uncratered regions
e. was likely formed by an uplift of Mars's crust
17. Uranium 235 decays to lead 207 with a half-life of around 700,000
years. A rock contains one-eighth of its original uranium. How old is the
rock?
a. 700,000 years
b. 1,400,000 years
c. 2,100,000 years
d. 2,800,000 years
e. 5,600,000 years
18. The reason the atmospheres of Venus and Earth have followed such
different evolutionary paths is _____ .
a. at birth, Venus was rich in carbon dioxide while the Earth was not
b. the Earth is more massive than Venus
c. Venus is closer to the Sun than is the Earth
d. the day is longer on Venus than it is on the Earth
e. Venus does not exhibit active plate tectonics
19. Of the following, which best describes the planet
most likely to have an atmosphere?
a. large mass, small radius, low temperature
b. low mass, small radius, low temperature
c. large mass, large radius, high temperature
d. low mass, large radius, high temperature
e. large mass, large radius, low temperature
20. The early atmosphere of Venus may have been as hot as 2,700 F because _____ .
a. of an anomalously large amount of carbon dioxide present in its atmosphere when it
was young
b. the Sun was much brighter 4.5 billion years ago
c. there was a large amount of water vapor in Venus's early atmosphere
d. it is believed that Venus developed a technologically advanced civilization in
its early history
e. Venus had an extensive Ozone layer when it was born
22. Near a subduction zone, we expect _______ .
a. to find large changes in the level of the oceans
b. to find active volcanism
c. to see the formation of volcanic island chains (like Hawaii)
d. to observe the creation of new continental crustal material
e. to see sea-floor spreading
24. The bulk of the carbon dioxide initially present in the
atmosphere of the young Earth _______ .
a. has been lost to space
b. is now contained in green plants and plankton
c. is now tied up in the crust of the Earth
d. is now contained in the oceans of the Earth
e. is now contained in the polar caps
25. Of the following statements about Venus, which is NOT correct?
a. The surface of Venus is young, less than 1 billion years old
b. There is an underabundance of craters with diameter less than 30
km on Venus
c. The surface of Venus is covered primarily by rolling plains
d. The surface of Venus may show signs of recent geological activity
e. Maxwell Montes, the largest shield volcanos on Venus, is also the largest volcano in
the Solar System
26. The Valles Marineris _____ .
a. was likely formed by water erosion, similar to how the
Grand Canyon formed
b. was likely formed by the impact of a protoplanet
that cracked Mars's lithosphere
c. is likely the remains of a large rift zone
d. is likely the remains of ancient subduction zone formed by Mars's
only oceanic plate
e. was formed by cracking that occurred during the formation of the
Tharsis Bulge
27. Lunar maria _______ .
a. resulted from the flooding of large impact basins by lava flows
b. have much higher crater densities than the surrounding
regions
c. are spread uniformly over the surface of the Moon
d. are unique to the Moon; they have no counterparts on
other planets
e. All of the above are correct statements about the lunar
maria
28. Strong evidence that the Moon was geologically active in the past comes
from the ____ .
a. mountains in the highland regions
b. existence of the continent-like highland regions
c. light color of the highland regions
d. maria
e. All of the above
29. The Ozone layer on the Earth ________ .
a. helps to protect the surface from Solar ultraviolet radiation
b. helps to trap water vapor in the lower atmosphere
c. supplies the heat that drives the convection that produces our weather
d. only a & b
e. a, b, & c
30. The Hawaiian island chain _______ .
a. is strong evidence for the recent collision of continental plates
b. was caused by a hot-spot in the mantle of the Earth and crustal motion
c. was created by a series of impacts of large objects
d. is evidence that the Moon was once part of the Earth
e. was formed in a manner similar to the Andes in South America
32. The oldest rocks on the Earth are around _____ old, according
to radioactive age dating.
a. 46,000 years
b. 200,000 years
c. 200 million years
d. 4.4 billion years
e. 460 billion years
33. Compared to the side of the Moon facing the Earth, the Lunar backside has
_____ .
a. more mountains
b. substantially fewer craters
c. substantially fewer mountain ranges
d. fewer maria
e. one active volcano, while the near side has none
34. The surface of Mercury bears the strongest resemblance to _____ .
a. that of the Earth
b. that of Venus
c. that of the Moon
d. that of Mars
35. The cratering density in the Lunar highlands and maria
tells us that _____ .
a. the Moon was geologically active in the past
b. the highlands are older than the maria
c. the cratering rate on the Moon has slowed down in the last billion years
d. large impacts like the dinosaur killer on the Earth, occur every 10
million years or so on the Moon
e. plate tectonic activity on the Moon continued until
the last billion years
36. Earth and Venus are often called sister planets. In what ways are
Venus and the Earth most alike? Earth and Venus have similar _____ .
a. atmospheric composition and density
b. size, density, and escape speed
c. surface temperature and atmospheric pressure
d. size, density, and atmospheric pressure
e. interior composition and atmospheric composition
37. A large difference between Mars's northern hemisphere and its southern
hemisphere is _____ .
a. the southern hemisphere appears to be older than the northern hemisphere
b. the northern hemisphere is, on average, at higher elevation than the
southern hemisphere
c. the southern hemisphere contains nearly all the volcanos and also contains
the largest volcano on Mars, Olympus Mons
d. the southern hemisphere is dominated by maria-like regions while the
northern hemisphere is more highland-like in character
e. the northern hemisphere is strong evidence of on-going plate tectonic
activity on Mars
39. Outflow Channels ______ .
a. are evidence for the existence of an early tropical climate on Mars
b. are evidence for sudden catastrophic floods on Mars
c. are evidence for active volcanism in the northern hemisphere of Mars
d. are evidence for high mountain lakes on Mars
e. are evidence for ancient canals on Mars
40. The troposphere is ________ in the Earth's atmosphere.
a. where we find the ionosphere
b. where the weather is generated
c. where the Ozone layer is located
d. one of the layers where the temperature increases as you move up in
altitude
e. the outermost layer
41. Oceanic crustal plates _____ .
a. are the youngest part of the surface of the Earth
b. cover about 55 % of the surface of the Earth
c. are subducted when they collide with a continental plate
d. can be created near rift zones
e. All of the above are correct
42. A comparison of the atmospheric pressures of Venus and the
Earth tells you _______.
a. the chemical compositions of the planets
b. the depth of the oceans on the planet
c. the escape velocities of the planets
d. the masses of the atmospheres of the planets
e. whether an ozone layer exists around the planet
43. The majority of Venus's surface is best described as _______ .
a. maria-like basins
b. highland regions
c. weird terrain
d. oceanic basins
e. rolling plains
47. The light-colored regions on the Moon are _______ .
a. highlands, the oldest and most heavily cratered regions on the Moon
b. ancient Lunar ocean basins
c. maria, lava-filled impact basins
d. large dust covered Lunar plains
e. mountain ranges produced during the era when plate tectonics
was active on the Moon
48. Which of the following statements about the surface of
Venus is NOT correct?
a. The surface of Venus is young, less than 1 billion years old
b. There is an underabundance of craters with diameter less than 30
km on Venus
c. The surface of Venus is covered primarily by rolling plains
d. The surface of Venus may show signs of recent geological activity
e. All of the above are correct statements about Venus.
49. Venus is very dry today with no liquid water on its surface. What happened
to Venus's oceans (liquid water)?
a. The water exists as water vapor in the upper atmosphere of Venus.
b. The water escaped to space after Venus was struck by a Mars-sized object that
caused the oceans to boil
c. Venus was not born with any water; it was always dry.
d. The water vapor rose to high altitudes where it was broken into hydrogen
and oxygen; the hydrogen escaped to space and the oxygen formed other
molecules and compounds
e. The water slowly seeped into the crust of Venus, where it formed a
permafrost layer and/or was incorporated into rocks in the mantle
of Venus
51. The Earth's atmosphere is composed _____ .
a. primarily of carbon dioxide and water
b. primarily of water with trace amounts of carbon dioxide
c. primarily of nitrogen but with a significant amount of oxygen
d. primarily of oxygen with trace amounts of carbon dioxide
e. primarily of oxygen with significant amounts of carbon dioxide and water
52. The portion of the northern Martian polar cap that remains in the
summer is composed of _____ while the seasonably variable
portion of the cap is
composed of _____.
a. water ice, water ice
b. carbon dioxide ice, carbon dioxide ice
c. water ice, carbon dioxide ice
d. carbon dioxide ice, water ice
e. water ice and frozen hydrogen, water ice
53. If the Ozone layer around the Earth was to disappear, then _____ .
a. the water vapor in our atmosphere would be slowly lost
b. the amount of ultraviolet radiation at the Earth's surface
would strongly increase
c. the thermosphere would also likely disappear
d. only a & b
e. a, b, & c
54. The cratering density in the Lunar highlands and maria
tells us that _____ .
a. the Moon was geologically active in the past
b. the highlands are older than the maria
c. the cratering rate on the Moon has slowed down in the last billion years
d. large impacts like the dinosaur killer on the Earth, occur every 10
million years or so on the Moon
e. plate tectonic activity on the Moon continued until
the last billion years
55. The current atmospheres of the Terrestrial planets are
most likely _______ .
a. the result of outgassing of materials trapped during the formation of the planets
b. the capture of many comets over the lifetime of the planets
c. the initial gases captured directly from the Solar Nebula 4.6 billion years ago
d. probably a combination of a & b
e. probably a combination of a, b, & c
56. The Gaia Hypothesis says _____ .
a. Venus is uninhabitable because of the Greenhouse Effect
b. the Earth is habitable because of the ionosphere and mesosphere
c. tidal forces led to the development of life on the Earth
d. the Earth is habitable because of life
e. life is possible because the Earth is habitable
57. Of the following, which best describes the
formation of 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 lava flows
d. massive volcanism followed by large impacts
e. uplifts and subsequent collapses of the lunar crust
58. Of the following statements about Mars, which is correct?
a. there has never been liquid water on Mars
b. space probes have found pools of water beneath the Martian surface
c. there are large lakes near the North pole of Mars
d. water ice probably exists in a permafrost layer below the surface of
Mars
e. It appears that Mars never had water in any form over its entire 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)
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
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
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 _____ .
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
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 3.6 kilometers
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 objects are geologically active today
d. The surface on all three objects may be considered permanent,
they are unchanging with time
Short Answer Questions--5 questions each worth 4 points.
1. 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?
2. What surface features and geologic events results from
Plate Tectonic activity?
What evidence and
facts led Wegener to propose the theory of plate tectonics? Why was the
theory not immeditately accepted? What eventually led to the acceptance
of the theory of plate tectonics?
3. 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?
4. Do we believe that Plate Tectonic activity occured
on Mars? Cite evidence that supports
your answer. What about Venus?
5. What methods were used to determine the ages of surface
features on the Moon? 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?
6. How does radar ranging work (on Venus by Magellan)?
What information can be obtained from
radar ranging?
7. Describe the Faint Young Sun Paradox. What is the resolution of the
Faint Young Sun Paradox?
8. Describe the Greenhouse Effect. What are the most important Greenhouse
gases on the Earth?
9. What is the water trap? Why is the water trap
important?
10. Venus, Earth, and Mars likely started out under similar conditions.
Describe the current thinking as to why each planet wound up so radically
different from each other (in terms of the atmospheres).
11. Mars does not support liquid oceanstoday. Is there water on Mars today? If
so, where is the water?
12. Briefly, contrast the surfaces on Venus and Mars. Do either Venus or
Mars show plate tectonic activity? If not, does this mean Venus and Mars do
not show signs of geology?
13. Describe why Mars is considered the best site for searches for
extra-Terrestrial life in our Solar System. Cite the reasons with the
observations of Mars which support your answer.
14. The primary attempts to address (Viking and ALH8401)
the question of life on Mars were made
by the Viking Landers and analysis of ALH8401.
Choose one and describe what was done and the results of the study.
as to whether it
showed or did not show life exists or existed
on Mars. Currently, where do we stand
on the question of life on Mars.