Skip to main content

About this free course

Download this course

Share this free course

Moons of our Solar System
Moons of our Solar System

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

1.7 Some other cryovolcanic moons

Cryovolcanism is not restricted to Enceladus. Other icy moons also show evidence of cryovolcanism.

The surface of Ariel (Figure 12) is thought to be the youngest of all of Uranus’ moons, having had the most recent geological activity. While it is unknown if it is currently active, it has been completely resurfaced since the beginning of the Solar System. The deep canyons seen in the image have been filled in and are possibly linear vents. Some similar features occur on Pluto’s largest moon, Charon.

Described image
Figure 12 Ariel

Figure 13 is Inverness Corona. This large corona is interpreted as an enormous cryovolcanic complex. It is one of three cryovolcanic complexes identified on Miranda.

Described image
Figure 13 Miranda

The smooth surface (shown in Figure 14) is thought to be of cryovolcanic origin with mounds and pits formed by ice flows. It has a thin, nitrogen atmosphere that is thought to have been created by the volcanic activity.

Described image
Figure 14 Triton

Next, try a short activity on some of what you’ve learned so far this week.

Activity 1 Moons volcanism

Timing: Allow approximately 15 minutes.

The heat source for cryovolcanism is likely to be:

a. 

Radioactive decay from the body’s centre


b. 

Tidal heating


c. 

Relic heat from the body’s formation


The correct answer is b.

b. 

Correct!


Inverness Corona is a massive volcanic complex on which moon?

a. 

Miranda


b. 

Ariel


c. 

Triton


The correct answer is a.

a. 

Correct. Inverness Corona is the chevron-patterned area apparent in most images of Miranda.


The volcanic activity on the Moon was mostly when?

a. 

3 million years ago


b. 

3 billion years ago


c. 

3 trillion years ago


The correct answer is b.

b. 

Well done.


Which of the following, when added to water-ice, lowers the melting temperature enough to allow the water-ice to melt in cryovolcanoes?

a. 

Sodium


b. 

Oxygen


c. 

Ammonia


The correct answer is c.

c. 

Correct. Ammonia is one of several substances believed to occur within icy moons that could lower the melting temperature of the ice.