Astronomy 1020 Exam 3: Review on Star Evolution, Planetary Formation, and Stellar Properti, Exams of Astronomy

Download Astronomy 1020 Exam 3: Review on Star Evolution, Planetary Formation, and Stellar Properti and more Exams Astronomy in PDF only on Docsity! Astronomy 1020 Exam 3 Review Questions 1. Describe the evolutionary sequence of star formation. What is a T Tauri star? A Herbig-Haro object? An accretion disk? Summarize how planetary formation is related to stellar formation. 2. Stars form in star clusters. Which are the oldest and which are the youngest star clusters in the Galaxy? What is an OB association? 3. What is meant by extrasolar planet? There are 4 techniques that are currently being used to search for extrasolar planets. List all 4 and describe each in detail. The majority of the recently discovered extrasolar planets have been found with one of these 4 techniques. Which is it? 4. In terms of energy production, what is significant about main sequence stars? Name the two reaction processes in hydrogen fusion and list the stellar mass where each is important. 5. What is ZAMS? What is true about the structure of M > 2M main sequence stars? 0.4M < M < 2M main sequence stars? M < 0.4M main sequence stars? 6. What are the 3 laws of stellar structure? What is meant by opacity ? 7. What is the lower mass limit of main sequence stars? The upper mass limit? Why are both of these numbers such as they are? What is a brown dwarf star? How is something classified as a star, brown dwarf, or planet? 8. Explain why the luminosity of a star scales as mass to the 4th power. (Hint : Think of central pressures and temperatures and how reaction rates depend upon these quanti- ties.) 9. Name the 3 different spectral classes of brown dwarfs. What characteristics must a brown dwarf process to be classified in each spectral class. 10. Explain how why are able to measure the age of a star cluster. Be specific and give details! 11. What is the Russell-Vogt Theorem? 12. Describe the ascent of a star up the red giant branch and in the red giant clump. What is meant by the helium flash? What is the triple alpha process and why is it important to life on Earth? 13. How are horizontal branch stars different from red giant clump stars? How are they the same in terms of stellar evolution? 1