Chapter #11 The Exobiology of Venus.


1. Why is Venus often referred to as Earth's Twin? What characteristic of Venus often also have it referred to as Earth's Evil Twin? (page 173)

2. How does the atmospheric pressure at the surface of Venus compare to that of Earth? (page 173)

3. How does the temperature at the surface of Venus compare to that of Earth? (page 173)

4. At the base of the thick cloud layer in Venus lower atmosphere the temperature and pressure is similar to that of Earth's surface. Why then is it highly unlikely that life could be present there? (page 173)

5. What is the average speed of the winds of Venus? How long would it take the atmosphere to complete a rotation around Venus at this speed? (page 175)

6. How long is an long is the period of a day (sunrise to sunrise) on Venus in terms of Earth days? (page 175)

7. Which takes longer on Venus, the time for the planet to complete on revolution about it's axis or the time to make one complete orbit around the sun? (page 175)

8. What is unique about the rotation of Venus as apposed to other planets in the solar system? (page 175)

9. If CO2 were the only greenhouse gas in the atmosphere of Venus would its surface be hotter or colder than current measurements? How much hotter or colder? (page 175)

10. What are the other gasses present in the atmosphere of Venus that contribute to its dramatic greenhouse effect? (page 175)

11. How do the total inventories of CO2 and N2 for Venus and the Earth compare? Where is it located for each planet? (page 175 &endash; 176)

12. How is Venus thought to have lost most of its water? Explain how the D/H ratio is used to support this line of reasoning. (page 176 and 178)

13. Describe process at play on Venus that has resulted in its high average temperature. (page 176 &endash; 177)

14. How much additional sunlight would the Earth have to receive or at what distance from the sun would the Earth need to be located in order to trigger a runaway greenhouse effect? (page 177)

15. What type of electromagnetic radiation and at what wavelength was used to survey the surface of Venus by the Magellan spacecraft? (page 179 &endash; 180)

16. Which type of surface (rough or smooth) on Venus did the Magellan spacecraft record as a bright portion of the radar images? (page 179 &endash; 180)

17. Why are there not craters on Venus's surface that are smaller that a few kilometers? (page 181)

18. What are the major geological processes on Venus that are responsible for the destruction of impact craters? What erosion or geological processes on Earth, that are responsible for removing impact craters, are not found on Venus? (page 181)

19. Describes the two possible scenarios given by Jakosky in which the climate of Venus could have allowed the existence of life at some time in the past. (page 190)