part a which of the following statements best describes...
TRANSCRIPT
Part A
Which of the following statements best describes the general pattern of composition among the four jovian
planets?
Hint A.1 Major categories of ingredients in planetary composition
The following table shows the four major categories of ingredient that were present in the solar nebula and
from which planets are made. Note that these categories are abbreviated in Figure 1 as “H, He” for hydrogen
and helium gas, and “H compounds” for hydrogen compounds.
ANSWER
:
Jupiter is made mostly of hydrogen, Saturn is made mostly of helium, Uranus is made
mostly of hydrogen compounds, and Neptune is made mostly of rock.
Jupiter is made mostly of hydrogen and helium, while the other three jovian planets
are made mostly of hydrogen compounds.
Jupiter and Saturn have compositions that are fairly different from the compositions of
Uranus and Neptune.
All four planets have essentially the same composition.
Correct
Jupiter and Saturn are made mostly of hydrogen and helium, while Uranus and Neptune are primarily made of
hydrogen compounds such as water (H2O), methane (CH4), and ammonia (NH3).
Part B
Look at the densities of the jovian planets given in Figure 1. Which of the following statements best describes
Process of Science: Tidal Heating
Learning Goal: To understand how we use our theory of gravity and tidal heating to explain observable
characteristics of the Galilean moons of Jupiter.
Introduction. Explore the Interactive Figure
before answering the questions. Be sure to note that the tidal stretching of Io is greatly exaggerated in the figure,
and Jupiter and the moons are not drawn to scale.
Part A
Io experiences tidal heating primarily because __________.
Sorting Task: Moons of Jupiter
Part A
Listed following are some of the distinguishing geological characteristics of the moons orbiting Jupiter. Match
each characteristic to the appropriate moon.
Hint A.1 What Jupiter's moons look like
Hint A.2 How does tidal heating affect these moons?
The moon that experiences the most tidal heating is _____.
ANSWER
:
Io
Europa
Ganymede
Correct
Remember that tidal heating makes Io quite hot inside. Use this fact to help you with the sorting task. Also
remember that Europa has the second-most tidal heating of these three moons.
Part A
Saturn’s rings are composed of __________.
ANSWER
:
gas from the early solar system
a series of solid concentric circles
lots of individual particles of ice and rock
parts of Saturn’s upper atmosphere being vented into space
Correct
Although Saturn’s rings appear solid when viewed from Earth, they are actually made of countless icy particles
ranging in size from dust grains to small boulders.
Part B
Multiple Choice Question 15
Part A
The belts and zones of Jupiter are
ANSWER
:
cyclonic and anticyclonic storms.
alternating bands of rising and falling air at different latitudes.
alternating regions of charged particles in Jupiter's magnetic field.
names for different cloud layers on Jupiter.
Correct
Multiple Choice Question 13
Part A
Why do the jovian planet interiors differ?
ANSWER
:
Accretion took longer further from the Sun, so the more distant planets formed their
The solar heating is less for the more distant planets than the closer planets.
The more distant planets had longer to form than the closer planets, since the solar
nebula lasted longer at greater distances from the Sun.
The more distant planets formed in a cooler region of the solar nebula and therefore
contain a greater proportion of ices than the closer jovian planets.
They differ due to giant impacts at the late stages of planet formation.
Correct
Multiple Choice Question 19
Part A
Why are there no impact craters on the surface of Io?
ANSWER
:
Io's thick atmosphere obscures the view of the craters.
It is too small to have been bombarded by planetesimals in the early solar system.
Any craters that existed have been eroded through the strong winds on Io's surface.
Jupiter's strong gravity attracted the planetesimals more strongly than Io and thus
none landed on its surface.
Io did have impact craters but they have all been buried in lava flows.
Correct
Multiple Choice Question 21
Part A
What causes synchronous rotation?
ANSWER
:
A massive planet exerts a tidal force on a moon that causes the moon to align itself
such that its tidal bulges always point toward and away from the planet.
Most jovian moons were formed out of their planet's nebula with the same rotational
period as their parent planet.
A massive planet exerts a tidal force on a moon that causes the moon to obtain the
same rotational period as its parent planet.
Most jovian moons were formed out of their planet's nebula with the same orbital
period.
Correct
Multiple Choice Question 23
Part A
What mechanism is most responsible for generating the internal heat of Io that drives the volcanic activity?
ANSWER
:
tidal heating
differentiation
radioactive decay
bombardment
accretion
Correct
Multiple Choice Question 25
Part A
Which moon has the most substantial atmosphere?
ANSWER
:
Ganymede
Europa
Io
Titan
Mimas
Correct
Multiple Choice Question 30
Part A
Why do astronomers believe Triton may have been a planet that was captured by Neptune?
ANSWER
:
It has an atmosphere and a measurable greenhouse effect.
It undergoes seasonal changes.
It is colder than any other moon or planet.
It orbits Neptune in the opposite direction of Neptune's rotation.
It is too large to have been formed in the jovian nebula that formed
Neptune.
Correct
Multiple Choice Question 32
Part A
Why are Saturn's rings so thin?
ANSWER
:
The "gap" moons shepherd the particles and maintain its thin profile.
Saturn's gravity prevents particles from migrating upwards out of the rings.
Solar radiation pressure keeps particles pressed into the rings.
The current thinness is a short-lived phenomenon that is special to this time.
Any particle in the ring with an orbital tilt would collide with other ring particles,
flattening its orbit.
Correct
Ranking Task: Distances of Meteorites, Comets, and Asteroids
Part A
Listed following are several objects in the solar system. Rank these objects from left to right based on their
distance from the Sun, from closest to farthest.
Hint A.1 What are Trojan asteroids?
Trojan asteroids are __________.
ANSWER
:
dark-colored asteroids found in the main asteroid belt
asteroids that cross Earth's orbit
asteroids that share Jupiter's orbit of the Sun
Correct
Because the Trojan asteroids share Jupiter's orbit of the Sun, they are the same distance from the Sun as
Hint B.1 How Is the period of an object’s orbit related to its distance from the Sun?
According to Kepler’s third law, an object that is farther from the Sun (larger semimajor axis) has __________.
ANSWER
:
a longer orbital period than an object closer to the Sun
a shorter orbital period than an object closer to the
Sun
the same orbital period as an object closer to the Sun
Correct
Use this fact with your answer to Part A, and you should be able to complete Part B successfully.
Part C
Listed following are several objects in the solar system. Rank these objects from left to right based on the distance
from the Sun at which they are presumed to have formed, from nearest to farthest.
Hint C.1 Where did Oort cloud comets form?
The comets of the Oort cloud are thought to have formed __________.
ANSWER
:
in the region where they are now located, far from the
Sun
in the same region as the Kuiper belt
in the same region as the jovian planets
Correct
After forming among the jovian planets, the Oort cloud objects were "kicked out" to their current orbits by
gravitational encounters with the large planets. In contrast, the asteroid belt objects and Kuiper belt objects are
thought to remain in the region where they formed.
Ranking Task: Understanding Comet Tails
Part A
The following figures show four positions (1-4) of a comet during its orbit of the Sun. Also shown is the orbit of
the Earth around the Sun. Rank the positions of the comet from left to right based on the size of its tail, from
shortest to longest. (Not to scale; tails not shown.)
Hint A.1 What determines tail length?
The length of a comet’s tail is determined primarily by __________.
ANSWER
:
how long it has been since the comet was at aphelion
the comet's distance from the Sun
whether the comet is approaching the Sun or moving away from the
Sun
Correct
With this fact in mind, you should now be able to complete Part A successfully.
Sorting Task: Comets, Meteors, and Asteroids
Part A
Listed following are some distinguishing characteristics of comets, meteors, and asteroids. Match these to the
appropriate category of objects.
Hint A.1 Where is the asteroid belt located?
The asteroid belt is located __________.
ANSWER
:
between Mars and Jupiter
from about the orbit of Neptune to about twice Neptune’s distance from the Sun
in a spherical region far beyond the orbit of Pluto
Correct
Now, remember that Mars is a little less than 2 AU from the Sun and Jupiter is about 5 AU from the Sun. Use
this fact to sort at least one item correctly.
Hint A.2 What are the Kuiper belt and Oort cloud?
The Kuiper belt and Oort cloud can be described as __________.
ANSWER
:
regions in which we find asteroids
regions from which comets enter the inner solar system
large groups of meteors
Correct
The existence of both the Kuiper belt and Oort cloud was both inferred from studies of comet orbits; these
regions are the places the comets come from.
Hint A.3 Where can you see a meteor?
Meteors can be viewed only __________.
ANSWER
:
on terrestrial planets
on worlds with atmospheres
in space
Correct
Meteors are phenomena that occur within an atmosphere. Use this fact to correctly sort the items that go with
meteors.
Multiple Choice Question 5
Part A
Why do asteroids and comets differ in composition?
ANSWER
:
Asteroids and comets formed at different times.
Asteroids formed inside the frost line, while comets formed
outside.
Comets are much larger than asteroids.
Asteroids are much larger than comets.
Comets formed from the jovian nebula, while asteroids did not.
Correct
Multiple Choice Question 3
Part A
A rocky leftover planetesimal orbiting the Sun is
ANSWER
:
a comet.
a meteorite.
an asteroid.
a meteor.
possibly any of the above
Correct
Multiple Choice Question 8
Part A
Which is closest to the average distance between asteroids in the asteroid belt?
ANSWER
:
10 million km
10 thousand km
100 thousand km
1 thousand km
1 million km
Correct
Multiple Choice Question 9
Part A
The combined mass of all the asteroids in the asteroid belt is
ANSWER
:
more than that of all the planets combined.
about the same as that of Jupiter.
about twice that of Earth.
about the same as that of Earth.
less than that of any terrestrial planet.
Correct
Multiple Choice Question 29
Part A
What part of a comet points most directly away from the Sun?
ANSWER
:
the dust tail
the jets of gas
the nucleus
the coma
the plasma tail
Correct