1.Summarize the evidence supporting the theory that the Cretaceous-Tertiary extinction, which includes the extinction of the dinosaurs, was precipitated to a significant degree by the impact of a meteorite.
2. What are the three primary ways in which a planet can have or acquire a Moon. What is the most probable origin of Earth's Moon? Given examples of moons that probably arose by the other two mechanisms
3. What is the Roche limit of a planet and its role in the formation of ring systems? What would happen to an astronaut who enters the Roche limit of a planet?
4. What are the defining properties of a dwarf planet? What extra condition must be satisfied in order for a dwarf planet to be a true planet?
5. Describe the position, layout and typical inhabitants of the Asteroid Belt, the Kuiper Belt and the Oort Cloud. What, in particular, are plutinos?
6. A comet often has two different tails. How are they created, of what do these tails consist and what determines their direction in space?
7. a) The dwarf planet, Ixion, has an orbit that ranges from 30.091AU out to 49.269 AU. Use Kepler's Laws of Planetary Motion to calculate the orbital period of Ixion.
b) Using the same technique, compute the maximum distance from the Sun of a long-period comet that has an orbital period of 1,500,000 years and a perihelion at 0.5 A.U.
(Hint for a) and b): Remember that the semi-major axis is the average of the distance at perihelion and aphelion.)
8. What are the photosphere, chromosphere and corona of the Sun? Describe some typical phenomenon observed on or in each. What are the various emission and absorption line spectra associated with these layers of the Sun? What is the solar wind, and of what does it consist. How is it related to the corona and coronal holes? How is it related to aurorae on Earth?
9. What are sunspots and how are they related to the Sun's magnetic field? Is the magnetic field stronger weaker in sunspots? How does the temperature in a sunspot relate to the temperature in the rest of the photosphere? Describe the role of the Sun's differential rotation in the formation of sunspots. Describe (briefly) the 22 year solar cycle, stating its essential features.
10. At one time, the protostar that became our Sun had a surface temperature of about 3000K and a radius about 25 times that of the present-day Sun. How much more (or less) luminous, compared to today, was our Sun when it was a protostar? At what distance would you have to be from the protostar for it to have the same brightness as the Sun seen from Earth today?