Precipitation on Titan
1. What is the main purpose of the lecture?
- A. To explore the possibility that life may have once existed on Titan
- B. To show how evidence of water on Titan was detected
- C. To discuss recent findings about precipitation on Titan
- D. To explain how the moons of Earth and Saturn have evolved similarly
2. Why does the professor mention the discovery of a large dark spot on the surface of Titan?
- A. To identify one reason scientists now think that it rains on Titan
- B. To point out the difficulty in distinguishing surface and atmospheric features on Titan
- C. To emphasize that surface winds have changed the landscape
- D. To show how lakes are detected on Titan
3. According to the professor, how does Titan’s ITCZ differ from that of Earth?
- A. Titan’s ITCZ does not result from the convergence of surface winds
- B. Titan’s ITCZ remains at the north pole most of the time
- C. The position of Titan’s ITCZ ensures that tropical precipitation occurs all year round
- D. The position of Titan’s ITCZ shifts from one polar region to the other
4. According to the professor, why are the atmospheric circulation patterns on Titan simpler than those found on Earth?
- A. Titan’s ITCZ keeps these patterns from becoming movable
- B. Titan rotate more slowly than Earth does
- C. Titan is a moon rather than a planet
- D. Titan’s hydrologic cycle involves methane rather than water
5. What does the professor say are likely results of the very low temperatures on Titan?
[CHOOSE 2 ANSWERS]
- A. Lakes of liquid methane can exist there.
- B. There is no possibility of life there
- C. Precipitation evaporates quickly there
- D. The ITCZ migrates widely there
6. What is the professor’s opinion regarding future research on Titan?
- A. Astronomers should concentrate for now on interpreting the data they have already gathered
- B. Future research may provide a different interpretation of Titan’s atmospheric properties
- C. It will probably be difficult to obtain funding for additional research missions to Saturn
- D. Future research will add to our understanding of conditions on Earth before life appeared
答案：C A D B AB D