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Astronomy Ch. 12 Saturn
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) If you could find a bathtub big enough for Saturn, the planet would:
A) catch fire, as liquid sodium reacts with water.
B) sink due to its metallic interior.
C) precipitate more helium.
D) explode due to its liquid metallic hydrogen.
E) float.
1)
2) Saturn's rings are widest open, doubling the planet's brightness, when it is at:
A) equinox.
B) quadrature.
C) greatest elongation.
D) opposition.
E) solstice.
2)
3) Saturn's rings are edge-on and vanish when it is at:
A) solstice.
B) opposition.
C) conjunction with the Sun.
D) equinox.
E) greatest elongation.
3)
4) The reason Saturn lost very little of its original atmosphere is due to its
A) ring system.
B) rapid rotation.
C) large mass.
D) many moons.
E) strong magnetic field.
4)
5) Saturn is noticeably oblate because
A) it has strong magnetic fields that deform its shape.
B) its powerful gravity acts stronger on the closer poles than the distant equator.
C) it is tidally distorted by the pulls for its satellite system.
D) it is a fluid body that is spinning rapidly.
E) All of the above are correct.
5)
6) The atmosphere of Saturn is composed mostly of:
A) methane and ammonia.
B) carbon dioxide and ethane.
C) hydrogen sulfide and ammonia.
D) nitrogen and oxygen.
E) hydrogen and helium.
6)
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7) What is the space probe that is currently orbiting Saturn and is responsible for numerous
discoveries of storms and weather patterns in Saturn's atmosphere called?
A) New Horizons.
B) Messenger.
C) Encke.
D) Cassini.
E) Galileo.
7)
8) The most abundant element in Saturn's atmosphere is
A) methane.
B) nitrogen.
C) hydrogen.
D) helium.
E) ammonia.
8)
9) Compared to Jupiter, Saturn's atmosphere is
A) more colorful with variations in color easily viewed from Earth.
B) more violent with larger storm phenomena easily viewed from Earth.
C) more calm with fewer disturbances or storms.
D) much thicker causing the visibility of the lower layers to be reduced.
E) more uniform with no significant variation in color in the lower cloud levels.
9)
10) Saturn's cloud surface appears more uniform than Jupiter's because
A) due to Saturn's greater distance from the Sun, the colorful cloud layers are just not visible.
B) it is composed of completely different gases than Jupiter's.
C) the cloud layers are thicker, allowing fewer holes to see the colorful layers.
D) there is a thick outer cloud covering of water ice overlying the colorful ices.
E) due to Saturn's lower gravity, the colorful cloud layers escaped.
10)
11) The wind speeds found in the bands and zones of Saturn, compared to those on Jupiter, are
about
A) 2 times faster.
B) 3 times faster.
C) 3 times slower.
D) the same.
E) 2 times slower.
11)
12) Compared to Jupiter, the motions observed in Saturn's atmosphere are
A) slower with fewer zone-belt alternations.
B) faster with fewer zone-belt alternations.
C) faster with more zone-belt alternations.
D) slower with more zone-belt alterations.
E) nearly identical.
12)
13) Saturn's bands, oval storm systems, and turbulent flow patterns are powered by:
A) convective motion and rapid rotation.
B) the fusion in Saturn's core.
C) a liquid metallic hydrogen interior.
D) the Greenhouse effect.
E) the tides of Titan.
13)
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14) At the surface of Saturn's atmosphere the strength of the magnetic field is
A) about the same as Mars' magnetic field at its surface.
B) about the same as Venus' magnetic field at its surface.
C) about the same as Earth's magnetic field at its surface.
D) about the same as Mercury's magnetic field at its surface.
E) about the same as Jupiter's magnetic field at its atmospheric surface.
14)
15) Why does the atmosphere of Saturn appear to have only half the helium content of Jupiter?
A) Because Saturn is so much colder, helium does not show up as strongly in its spectrum.
B) Saturn was formed farther from the helium rich Sun.
C) Much of Saturn's helium has differentiated towards its center.
D) A red dwarf, Jupiter has fused some of its hydrogen into helium, whereas Saturn, a colder
planet, has not.
E) Much of Saturn's helium has reacted with water and formed helium oxide.
15)
16) Why does Saturn radiate even more excess energy than Jupiter?
A) Saturn's thick cloud layer contributes to a larger greenhouse effect.
B) Saturn can fuse hydrogen into helium in its core, like the Sun.
C) Saturn is still radiating heat left over from its formation.
D) Helium rain gives off heat as it differentiates toward Saturn's center.
E) Saturn's atmosphere contains much methane, creating a large Greenhouse effect.
16)
17) What are Saturn's rings?
A) a glowing, flat magnetospheric auroral display
B) small icy particles moving in orbit around Saturn
C) a great disk of liquid helium
D) large rocky boulders moving in orbit around Saturn
E) a solid thin disc of material encircling Saturn
17)
18) What did the Voyager mission discover about the main rings of Saturn?
A) They are composed of tens of thousands of narrow ringlets.
B) There are hundreds of small moons in the ring system.
C) The ring system is much thicker than originally believed.
D) They were less dense than the rings of Jupiter.
E) There are several small moons inside the inner-most ring.
18)
19) The reason the rings of Saturn exist is because:
A) the gravitational influence of Titan confines them to those orbits.
B) there has not been sufficient time for the ring particles to form a moon.
C) Saturn's rapid rotation is spinning material away from its equator, out into space.
D) the eruptions of Mimas' volcanoes are keeping them supplied with ice.
E) the ring material lies within the Roche limit of Saturn.
19)
20) The Roche limit is the point at which
A) the mass of an object classifies it as a moon.
B) the external tidal forces on an object become greater than the internal forces that hold it
together.
C) a moon orbiting a planet experiences synchronous rotation.
D) the internal forces that hold an object together weaken so that the object falls apart.
E) the external tidal forces on an object are strong enough to be felt by the object.
20)
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21) Why are Saturn's rings so noticeable?
A) The particles in the rings are highly polished from numerous collisions with other
particles.
B) They are made of lots of fresh, bright icy particles from a recent breakup.
C) They are made of nitrogen frost, like the bright surface of Triton.
D) They are made of metallic hydrogen.
E) Saturn is so bright, the rings reflect a lot of light from both Saturn and the Sun.
21)
22) Which of the following played the most important role in the ring's formation?
A) tidal resonance with Titan
B) Saturn's distance from the Sun
C) debris from volcanoes on Mimas
D) Saturn's differential rotation
E) Saturn's Roche limit
22)
23) Shepherd satellites are defined as:
A) satellites in the coma of a comet.
B) moons that follow the exact orbit of another, larger, moon.
C) moons that orbit inside the system of rings.
D) moons that confine a narrow ring.
E) a type of moon that orbits another moon.
23)
24) What did the Voyager mission discover about Cassini's Division?
A) It is completely filled with a ring of very dark material.
B) It is actually completely empty of all ring material.
C) It contains several ringlets.
D) It actually contains one or more moons.
E) The spokes originate from it.
24)
25) While Galileo saw Saturn as a changing oval, the real nature of the rings was discovered by:
A) Huygens.
B) Newton.
C) Cassini.
D) Lowell.
E) Halley.
25)
26) A moon that goes inside the Roche Limit will
A) be torn apart by the planet's tidal forces.
B) escape its planet's gravity.
C) get heated by the strong magnetic fields.
D) become a planet.
E) collide with a major satellite.
26)
27) The shepherd moons keep the ring particles in their rings by
A) attracting the ring particles, causing them speed up.
B) repelling the ring particles, causing them to speed up or slow down.
C) both attracting and repelling the ring particles, causing them to speed up or slow down.
D) repelling the ring particles, causing them to slow down.
E) attracting the ring particles, causing them to speed up or slow down.
27)
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28) When Voyager 2 was routed to fly by Saturn, it was originally the plan to have the satellite fly
through the Cassini gap. Why would this have been a bad idea?
A) That route would have taken Voyager 2 inside Saturn's magnetic field causing the
electronics on board to be destroyed.
B) The gaps in Saturn's ring system (including the Cassini gap) are not actually empty space,
rather they are an area of low density in the rings.
C) Voyager 2 would have encountered density waves which would have crushed the
satellite.
D) That route would have taken Voyager 2 within the Roche Limit and the satellite would
have been torn to pieces.
E) The Cassini gap actually contains a large moon that orbits Saturn with a very high speed
and Voyager 2 would have collided with that moon.
28)
29) If satellite A is in a 2:1 resonance with satellite B, this means that
A) the orbit of satellite B takes twice as long to complete as that of satellite A.
B) satellite A completes one orbit for every two orbits of satellite B.
C) satellite A moves twice as fast as satellite B.
D) satellite A is twice as large as satellite B.
E) satellite B spins on its axis one time for every two orbits of satellite A.
29)
30) Why do scientists think the Cassini spacecraft did not observe "spokes" on the rings during the
first year of its visit with Saturn?
A) To see the "spokes", a particular alignment of the rings with the Sun is necessary and it
took one year for that alignment to reoccur.
B) The Cassini spacecraft was not looking in the right part of Saturn's ring system to see the
"spokes".
C) The "spokes" are related to Saturn's magnetic field and the Cassini spacecraft was located
inside Saturn's magnetic field, while Voyager 2 was not.
D) The "spokes" observed before were a phenomenon of the Voyager 2 camera.
E) The "spokes" are not a regular phenomenon of Saturn's rings. They occur only in certain
seasons.
30)
31) Shepherd moons were discovered because scientists hypothesized their existence after observing
A) the narrow F Ring.
B) the backlit E Ring.
C) the Cassini Gap.
D) that the gaps are not empty space, but low density regions of material.
E) the spiral density waves in the ring system.
31)
32) Cassini is:
A) a gap in the rings created by a resonance with Mimas.
B) the French astronomer who first discovered a gap in Saturn's rings.
C) NASA's orbiter now taking photos of Saturn.
D) all of the above
E) none of the above
32)
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33) How many large moons does Saturn have?
A) 3
B) 1
C) 0
D) 4
E) 2
33)
34) Rhea, Saturn's second largest moon, might best be described as:
A) orbiting in a highly elliptical orbit, far from Saturn.
B) being the only major moon of any planet not in synchronous rotation.
C) having a very reflective, icy surface that is heavily cratered.
D) being composed of the densest material of any saturnian moon and dark in appearance.
E) having the leading hemisphere six times darker than the following one.
34)
35) Titan is an interesting moon because:
A) beneath its clouds, Titan may be Earth-like, with liquid water.
B) it has a rich atmosphere that may resemble that of the early Earth.
C) the Huygens rover has sent back images of sedimentary rocks there.
D) it is known to have ice volcanism on its surface.
E) all of the above
35)
36) What evidence suggests that Enceladus has ongoing geological activity?
A) Voyager 1 showed sulfur eruptions all over its pizza-pie colored surface.
B) Lack of impact craters on much of its surface and evidence of ice flows from possible
volcanic activity.
C) Enceladus undergoes severe tidal stresses from its resonance with Titan.
D) Voyager 2 photographed liquid nitrogen geysers 10 kilometers tall.
E) Enceladus is located within Saturn's Roche limit, and ready to blow up.
36)
37) The atmosphere of Titan is composed mostly of:
A) methane.
B) oxygen.
C) carbon dioxide.
D) nitrogen.
E) hydrogen.
37)
38) The asymmetrical surface markings on some of Saturn's moons are probably due to:
A) the moons of Saturn are made primarily of ices.
B) in most cases, the moons are tidally locked by Saturn's gravity into synchronous rotation.
C) all of the moons are located within the rings and they sweep up ring particles.
D) comet impacts become progressively harder as you get closer to Saturn.
E) most of the moons show signs of ice volcanism driven by tidal interactions.
38)
39) How many medium-sized moons does Saturn have?
A) too many to count
B) 1
C) 6
D) 18
E) 9
39)
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40) What is interesting about Saturn's large moon Titan?
A) It has its own moon.
B) It is one of Saturn's two large moons.
C) It has an atmosphere.
D) It has a 2:1 resonance with Mimas and a 4:1 resonance with the Cassini gap.
E) It orbits Saturn in a retrograde sense.
40)
41) Why was it thought that Titan may have oceans of methane?
A) The abundance of hydrocarbons in the atmosphere of Titan, led scientists to believe that
Titan had an abundance of methane on its surface.
B) Titan's atmosphere contains traces of methane. Similarly, Earth's atmosphere contains
traces of water vapor. So, scientist thought Titan should have methane oceans.
C) Since Saturn has methane ice in its atmosphere, methane should be abundant in this
region of the solar system. The sheer abundance of methane in the region led scientists to
hypothesize methane oceans on Titan.
D) The atmospheric pressure at Titan's surface and its surface temperature are such that
methane should be liquid on Titan's surface.
E) Titan's atmosphere is like Earth's (mostly nitrogen), but its temperature is too low for
water to be in the liquid phase. The only other possible liquid was methane.
41)
42) Why do scientists think Titan has an atmosphere while the large moons of Jupiter (Ganymede,
Callisto, Europa and Io) do not?
A) The jovian satellites experienced too many collisions in their lifetimes to maintain
atmospheres.
B) The jovian satellites had their atmospheres stripped by Jupiter's gravitational pull.
C) The jovian satellites lost their atmospheres because of Jupiter's thermal radiation.
D) Titan got its atmosphere by accreting gases from Saturn. The jovian satellites were
competing with one another to do this, so it was unsuccessful for any of them.
E) The jovian satellites never formed atmospheres because the solar nebula was too hot
there.
42)
43) What did the Huygens and Cassini probes find on the surface of Titan?
A) rocks and no water
B) lakes and oceans of water
C) methane oceans
D) no methane, no water; just rocks
E) an ocean of some unknown liquid and methane lakes
43)
44) The "wispy terrain" on Rhea was revealed by the Cassini spacecraft to be
A) ice cliffs created by tectonic fractures.
B) water ice flows from geyser-like activity.
C) water ice flows from past impacts that cracked its icy surface.
D) the icy ash of water volcanoes.
E) "maria" created during the period of high impacts.
44)
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45) The Cassini spacecraft found evidence that the E Ring is related to Enceladus through
A) the deposition of gases from Enceladus on the particles of the E Ring making them more
reflective as the gas condenses on the particles.
B) the impact history of Enceladus -- a major impact caused parts of the moon to be ejected
from the surface and cross the Roche Limit to become the E Ring.
C) the gravitational interactions by Enceladus on the particles in the E Ring.
D) their common origin: both the E Ring and Enceladus have a common "ancestral" comet
parent.
E) a continual supply of icy particles spewed via volcanism on Enceladus.
45)
46) Which Saturnian moon has the leading hemisphere black as tar, the back side icy white?
A) Mimas
B) Rhea
C) Iapetus
D) Enceladus
E) Titan
46)
47) While not yet observed in eruption, it is likely that ________ has active volcanoes; it certainly has
one hemisphere greatly reworked by tectonic and volcanic forces.
A) Mimas
B) Dione
C) Titan
D) Rhea
E) Enceladus
47)
48) What mission landed on Titan in early 2005?
A) Galileo's probe
B) Cassini orbiter
C) New Horizons
D) Rover Spirit
E) Huygens
48)
49) What makes Mimas a distinct moon?
A) It has a rich atmosphere that may resemble that of the early Earth.
B) The leading hemisphere is very dark, while the back side is bright ice.
C) It helps maintain a wide apparent gap in Saturn's rings, known as Encke's Division.
D) It is the largest of Saturn's moons.
E) It suffered a huge meteorite impact that must have nearly shattered it.
49)
50) Which moon of Saturn constantly changes its rotational speed and rotational axis?
A) Calypso
B) Janus
C) Mimas
D) Hyperion
E) Iapetus
50)
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