29:52 Homework Set #3

Assigned: October 10, 2004

Due: October 18, 2004

If you have questions about these problems, contact me for clarification or help. You should also communicate with your classmates via the bulletin board.

1. Find a picture of a Martian Valley Network Channel, either in the textbook or online. Compare it in size to rivers here in Iowa or the Midwest. I only want an approximate analysis, but be sure to describe what you are doing.
2. What observations do we have that show that Mars possesses an atmosphere?
3. What important conclusion do we draw from the fact that impact craters are seen on some areas of the Martian surface?
4. Is it possible that you could observe Venus closer to the Sun on the sky (i.e. a smaller angular separation) than the planet Mercury? Support your answer with a written explanation, or a diagram showing the orbits of the two planets. The diagram is the easier and more illuminating way of approaching this problem, but may be a little harder to submit. The choice is yours. If you submit your homework as a MS Word file, and don’t want to include graphics files, at least draw the diagram to work on the problem, then describe what you have found in words.
5. Using information in your textbook or on the web, come up with an argument in support of the statement in the book that the geological feature Aphrodite on Venus is about the same size as Australia on Earth.
6. Explain why a comparison of Aphrodite and Australia makes sense scientifically.
7. Use the “solar system simulator” at http://space.jpl.nasa.gov to find the current distance to Venus. In this problem, I want a precise distance good to about three significant figures.
8. If you were to send a radio signal to a spacecraft at Venus, and it was to immediately respond, how long would you have to wait between transmission and reception of the reply? Hint: Radio waves travel at the speed of light.