What are the moons of the outer planets made of, and how is their composition different from that of our Moon?
Compare the geology of Callisto, Ganymede, and Titan.
What is the evidence for a liquid water ocean on Europa, and why is this interesting to scientists searching for extraterrestrial life?
Explain the energy source that powers the volcanoes of Io.
Compare the properties of Titan’s atmosphere with those of Earth’s atmosphere.
How was Pluto discovered? Why did it take so long to find it?
How are Triton and Pluto similar?
Describe and compare the rings of Saturn and Uranus, including their possible origins.
Why were the rings of Uranus not observed directly from telescopes on the ground on Earth? How were they discovered?
List at least three major differences between Pluto and the terrestrial planets.
The Hubble Space Telescope images of Pluto in 2002 showed a bright spot and some darker areas around it. Now that we have the close-up New Horizons images, what did the large bright region on Pluto turn out to be?
Saturn’s E ring is broad and thin, and far from Saturn. It requires fresh particles to sustain itself. What is the source of new E-ring particles?