Question 1

Callisto, the outer Galilean satellite of Jupiter, has a surface consisting of:

Accepted Answer

Callisto's surface is characterized by an ancient, icy crust that is heavily cratered. Unlike some other moons in the solar system, it shows no signs of surface cracks or groove belts that would suggest geological activity beneath the surface.

Question 2

What have we learned about the atmospheres of the Galilean satellites of Jupiter?

Accepted Answer

Callisto and Ganymede, two of the Galilean satellites, have been discovered to possess thin atmospheres. Callisto's atmosphere contains carbon dioxide, while Ganymede's atmosphere includes oxygen.

Question 3

Why do we suspect the existence of some liquid beneath the surface of Callisto?

Accepted Answer

Callisto's induced magnetic field, detected during spacecraft flybys, suggests the presence of a subsurface salty ocean that conducts electricity, thus generating the observed magnetic field as Callisto moves through Jupiter's magnetosphere.

Question 4

The spacecraft Galileo and its predecessors left many questions about Callisto unanswered. Which one of the following questions was answered by these flyby missions?

Accepted Answer

The flyby missions of Galileo and its predecessors confirmed that Callisto does not have an atmosphere.

Question 5

All of the following exist on Titan EXCEPT:

Accepted Answer

While there is evidence of liquid oceans and rivers beneath the surface, there is no evidence of liquid water on the surface of Titan.

Question 6

Which of the following satellites of planets in our solar system has a significant, dense atmosphere?

Accepted Answer

Titan has a significant, dense atmosphere mostly made up of nitrogen with some methane and other trace gases. The other options listed do not have significant atmospheres.

Question 7

Titan is Saturn's largest satellite. It is unusual among all the planetary satellites because of its:

Accepted Answer

Titan is the only satellite in our solar system known to have a dense atmosphere, which is mostly made up of nitrogen and contains small amounts of methane and other gases.

Question 8

Which of the satellites of the giant planets is known to have a significant atmosphere?

Accepted Answer

Titan is known to have a significant atmosphere mainly composed of nitrogen, with trace amounts of methane and other gases. Callisto, Europa, and Triton have thin atmospheres composed mainly of gases released from their surfaces due to bombardment by charged particles from the Sun.

Question 9

Nitrogen (N₂) makes up about 95% of Titan's thick atmosphere. What gas makes up most of the remaining 5% of the atmosphere?

Accepted Answer

Methane (CH4) is known to be the second most abundant gas in Titan's atmosphere, making up most of the remaining 5%. While small amounts of other gases have also been detected, methane is the most significant component after nitrogen.

Question 10

How is nitrogen thought to have become the dominant gas in the atmosphere of the satellite Titan?

Accepted Answer

The dominant theory suggests that Titan's nitrogen atmosphere originated from the breakup of ammonia (NH3) into nitrogen (N2) and hydrogen (H2), with the hydrogen being light enough to escape Titan's gravity into space. This process left behind a nitrogen-rich atmosphere.

Question 11

In what way was methane, CH₄, first discovered on Titan, the giant satellite of Saturn?

Accepted Answer

Methane was first discovered on Titan by observing specific absorptions in the reflected sunlight through spectroscopy. This allowed scientists to analyze the composition of Titan's atmosphere and identify the presence of methane.

Question 12

Which chemical in the atmosphere of Titan (a satellite of Saturn) appears to play the same role that water plays upon Earth in producing "rain" and forming lakes and streams, at the temperature encountered on the satellite?

Accepted Answer

Methane plays the same role on Titan as water does on Earth, forming lakes, streams, and rain at the lower temperatures found on the satellite.

Question 13

How were the hydrocarbon lakes of Titan discovered?

Accepted Answer

Radar maps made by Cassini to measure the height of the terrain revealed many flat areas that were consistent with liquid surfaces, leading scientists to infer that these areas were hydrocarbon lakes.

Question 14

What would be a typical weather forecast on Titan, Saturn's largest satellite?

Accepted Answer

Titan's atmosphere is primarily composed of nitrogen, and it is known for its dense hydrocarbon fog and methane rain, distinguishing its weather patterns from those of Earth and other celestial bodies.

Question 15

What is the atmospheric pressure at the surface of Titan, Saturn's largest satellite? (one atmosphere = air pressure at sea level on Earth)

Accepted Answer

The atmospheric pressure at the surface of Titan is approximately 1.5 atmospheres, which is slightly higher than the air pressure at sea level on Earth.

Question 16

The atmospheric pressure at the surface of Titan, Saturn's largest satellite, is 1 1/2 atmospheres (i.e., 1 1/2 times the air pressure at sea level on Earth). How much mass is contained in the atmosphere above a square meter of Titan's surface compared to the mass above a square meter of Earth's surface?

Accepted Answer

The answer of The atmospheric pressure at the surface of...

Question 17

What is thought to exist in both gas and liquid states in Titan's atmosphere, where small variations in temperature and pressure contribute to weather processes similar to the hydrological cycle on Earth?

Accepted Answer

Small variations in temperature and pressure contribute to weather processes similar to the hydrological cycle on Earth in Titan's atmosphere. Methane exists in both gas and liquid states in Titan's atmosphere and plays a crucial role in its weather patterns.

Question 18

What are the physical characteristics of the "other" (non-Galilean) satellites of Jupiter?

Accepted Answer

The "other" (non-Galilean) satellites of Jupiter are generally less than about 200 km in diameter and are irregular in shape, distinguishing them from the larger, spherical Galilean moons.

Question 19

Most of the satellites of Jupiter beyond the innermost eight appear to be:

Accepted Answer

Most of Jupiter's outer satellites are believed to be captured asteroids or comets, as they have irregular shapes and orbits that suggest they did not form in place.

Question 20

For which of the following objects is the orbital motion (direction of motion around the orbit) retrograde?

Accepted Answer

Most of the satellites of Jupiter beyond the innermost eight have retrograde orbital motion, meaning they orbit in the opposite direction of Jupiter's rotation.

Quiz 13: Jupiter and Saturns Satellites of Fire and Ice