L2：
讲座
1. What is the main purpose of the lecture?
To discuss similarities in how Earth’s Moon and Io originally formed
To compare and contrast Jupiter’s four Galilean moons
To explain why Io differs so greatly from Earth’s Moon
To demonstrate how tidal forces affect Jupiter
2. What discovery by the Voyager spacecraft does the professor mention?
Io is volcanically active
Io has several large impact craters
Io’s orbit is highly irregular
Io is closer to Jupiter than previously thought
3. What effect of Jupiter’s gravitational force does the professor emphasize?
It causes variations in the shape of lo’s surface
It causes variations in lo’s rate of spin
It causes ocean levels on Io to rise and fall
It keeps the same side of Io always facing Jupiter
4. What factors does the professor mention that help explain Io’s internal heat?（多 选题）
Two of Jupiter’s other moons affect lo’s orbit.
Io still retains much of the internal heat that it had when it formed.
Heat radiating from Jupiter is absorbed by lo’s rocky surface.
Rock movement in Io’s interior causes friction.
5. What do the findings of the study of Europa and Ganymede imply?
Io’s orbit will gradually become more irregular
Volcanic activity on Io will eventually decrease
Jupiter’s gravitational pull on Io will weaken
D. Europa and Ganymede will move closer to Jupiter
6. Why does the professor say this:
To indicate that he does not like to be interrupted
To confirm the student’s conclusion
To remind the student that the point was covered in a previous class
D. To indicate that he wanted to change the topic
