Question 1

What is unusual about Triton's orbit around Neptune?

Accepted Answer

Triton is the only large moon in the solar system to orbit in the opposite direction to its host planet's rotation, making it unique in the solar system.

Question 2

What is the best explanation for the narrowness of the rings of Uranus and Neptune?

Accepted Answer

The narrowness of the rings of Uranus and Neptune is primarily due to the presence of small shepherd moons. These moons exert gravitational forces that confine the ring particles, maintaining their narrow structure.

Question 3

The reddish particles in Jupiter's rings are less than 1 percent as reflective as Saturn's whiter particles.Based on this information,what can you conclude about the composition of the ring particles?

Accepted Answer

The reflectivity of particles is often related to their composition. Icy particles tend to be more reflective (whiter), while rocky particles are less reflective (darker). Therefore, Saturn's whiter particles are likely icy, and Jupiter's less reflective particles are likely rocky.

Question 4

Which of the following has an atmosphere composed of mostly nitrogen with some methane?

Accepted Answer

Titan, the largest moon of Saturn, has an atmosphere primarily composed of nitrogen (about 98.4%) with some methane (about 1.6%).

Question 5

-The graph plots the escape velocity of several solar system objects along the vertical axis and the surface temperature along the horizontal.The lines plotted in the figure are the fastest speeds of gas particles as a function of temperature for various gases.Which of the gases plotted in this diagram could be retained by Ganymede?

Accepted Answer

The answer of 
-The graph plots the escape velocity of...

Question 6

-The graph plots the escape velocity of several solar system objects along the vertical axis and the surface temperature along the horizontal axis.The lines plotted in the figure are the speeds of the fastest gas particles as a function of temperature for various gases.Which of the objects in this diagram has the highest surface temperature?

Accepted Answer

The answer of 
-The graph plots the escape velocity of...

Question 7

-The diagram shows a cross-section of the interior of Uranus.Which region do current computer models suggest is composed primarily of liquid water? Hint: The lowest pressure regions will be gaseous.

Accepted Answer

Region 2 is typically considered the layer composed primarily of water, ammonia, and methane ices, often referred to as the "icy mantle" in models of Uranus's interior.

Question 8

What causes some rings of Saturn to be narrow,as seen in space probe photos?

Accepted Answer

Small shepherd moons orbit near the rings and their gravitational influence helps to maintain the narrowness of the rings by confining the particles within certain boundaries.

Question 9

Why do Uranus and Neptune appear blue or blue-green?

Accepted Answer

Traces of methane in the atmosphere of Uranus and Neptune absorb red light very efficiently, leaving behind only the blue and green wavelengths to be scattered and give a blue or blue-green appearance.

Question 10

In what way is the rotation of Uranus peculiar?

Accepted Answer

Uranus has an unusual tilt, with its axis nearly parallel to the plane of its orbit, causing it to rotate on its side.

Question 11

Which of these planets has the most featureless appearance,as revealed visually by space probes?

Accepted Answer

Uranus appears to have the most featureless appearance as revealed visually by space probes. This is due to its hazy, blue-green atmosphere and lack of visible cloud bands or distinct features on its surface.

Question 12

Which of the following are found on Triton?

Accepted Answer

Triton, Neptune's largest moon, has a thin nitrogen atmosphere.

Question 13

Which of these is (are)aligned with the orbital plane of Uranus?

Accepted Answer

The answer of Which of these is (are)aligned with the...

Question 14

On its icy surface,Uranus's satellite Ariel has smooth valleys with few craters,as well as rough areas with many craters.Based on this,what can be concluded?

Accepted Answer

The smooth valleys with few craters suggest they are younger surfaces, as they have experienced less impact over time. The rough areas with many craters indicate they are older, having accumulated more impacts.

Question 15

How are the magnetic fields of Uranus and Neptune peculiar?

Accepted Answer

The magnetic fields of Uranus and Neptune are peculiar because they are highly inclined to their planet's axis of rotation, which is different from the magnetic fields of other planets, including Earth. For Uranus, the magnetic axis is tilted by about 60 degrees, while for Neptune, it is tilted by about 47 degrees.

Question 16

How can we be sure that the particles in the rings of Neptune are very small?

Accepted Answer

The rings of Neptune are bright in forward scattered light, which indicates that they are composed of small particles. Small particles scatter light more effectively in the forward direction, making the rings appear brighter when observed in this way.

Question 17

When were the rings of Uranus discovered?

Accepted Answer

The rings of Uranus were discovered during an occultation of a star by the planet and its rings in 1977.

Question 18

Which of the following does Jupiter lack?

Accepted Answer

Jupiter lacks crustal plates on its surface because it is a gas giant and does not have a solid surface like terrestrial planets.

Question 19

Which of the following is a satellite of Pluto?

Accepted Answer

Charon is the largest and only known satellite of Pluto. Miranda is a moon of Uranus, Eris is a dwarf planet similar to Pluto, and Nereid is a moon of Neptune.

Question 20

Why do Uranus and Neptune contain no liquid metallic hydrogen?

Accepted Answer

Liquid metallic hydrogen forms in planets with sufficient mass and pressure, and Uranus and Neptune may not have enough mass to create it.

Quiz 14: Comparative Planetology of the Jovian Planets