Characteristics and Origins of the Solar System

Third Homework Set

October 6, 2000; Due: October 13, 2000

This time I’m serious! I swear I mean it this time!

1. This evenings the planet Uranus is due south at about 9PM in the constellation of Capricornus. Look at the images of the moons of Uranus, Titania and Mirana, on the attached web page. What can you say (in about a paragraph or two) about the geological history of these objects?
• Picture of Miranda
• Picture of Titania
2. The solar elongation of Venus is now 31.5 degrees. The solar elongation is the angle between the Sun and Venus, or more exactly the angle Venus-Earth-Sun, with the Earth as a vertex. Using information in the textbook, determine the distance of Venus from the Earth. You may either use a geometric approach, carefully drawing the triangle and making measurements, or use analysis with the law of cosines.
3. Given the answer to #2, and information in the book, what is the angular diameter of Venus? Compare it to the angular diameter of the Moon. I will give a short tutorial on angular measures in class. It isn’t difficult.
4. Based on what we have discussed in class, do you think the crater Kepler (on the Moon) is a fairly recent (geologically speaking) crater or a very old one? How about the crater Piccolomini? You can answer this one!
5. The Imbrium basin on the Moon is about 700 kilometers in diameter. Approximately how large was the impacting object that formed it?

Reminder: None of these problems is fundamentally difficult, but they usually involve one key idea that you need to proceed. If you are stumped, please come see me. I expect students to have questions about these, and consider it a crucial part of the teaching process.