Topics and questions for astro presentations

Transcription

1 Topics and questions for astro presentations 1. Historical development of distance measurements 1. Explain the challenges of identifying the distance to a point light source. What affects brightness? 2. When was the parallax method developed and what affects its accuracy? 3. When were different standard candles established? 4. Describe a timeline for the distances we could measure up until the present 2. Cepheid variables 1. What led to the discovery of Cepheid variables? Where were they first found? 2. What is one explanation for why they have periodic changes in intensity? 3. What conditions might be needed for a Cepheid variable to form? 3. Standard candles 1. What are the standard candles currently utilized in astronomy? Describe what each is in terms of the stellar lifecycle. (Cover at least 4) 2. What influences errors in astronomical measurements? 3. What are some false positives that can lead to incorrect distance measurements using standard candles? 4. Search for exoplanets 1. Describe how the methods to search for exoplanets have developed over time. 2. What are the sampling biases associated with the different methods and how are they accounted for in the final counts? 3. How can we determine the composition of an exoplanet? 5. Pre- solar system 1. How many stars went into forming the gas cloud that formed the solar system? 2. What is left of those stars? 3. How has the stellar neighborhood changed? 6. Early Solar System: 1. How big was the cloud that formed the sun and solar system? 2. What is gravitational collapse and what does it have to do with planet formation? 3. Why doesn t stuff fall into the sun? What is the role of angular momentum? 7. Late Solar system:

2 1. What will happen to the sun? What changes when a star becomes a red giant? 2. What will happen to the earth? 3. What is the ultimate fate of the solar system? 8. Inner planets: 1. What causes the composition of the inner planets? 2. Why do two have thick atmospheres, and the other two have none or very thin atmospheres? 3. How do their topographies compare and what causes that difference? 9. Outer planets: 1. What causes the composition of the outer planets? 2. Easy question: Talk about the scale of these planets 3. What are the rings around the outer planets and what made them? 4. What is the weather like on the outer planets and what drives the weather? (Does it work the same as on earth?) 10. Sun: 1. Where does fusion take place in the sun and what are the different layers? 2. How does heat flow in the sun? 3. What can we see of the sun, and how can we find things out about whats going on inside? 4. Why is the corona so hot? 11. Moons: 1. What are the different ways a planet may have/acquire a moon? 2. Are there any moons that are promising for life? 3. What s up with Neptune s moons Triton and Nereid? What does their motion say about their origin? 4. How are rings related to moons? 12. Our Moon: 1. Why are there areas of more or less cratering on our moon? (why isn t it all the same?) 2. Why do we think the moon is a result of a relatively early impact? (what s the evidence?) 3. What will be the ultimate fate of the moon? 13. Asteroid and Kuiper Belt 1. What does it mean to clear the neighborhood? 2. What is the Nice model and what does it have to do with the Kuiper belt?

3 3. What are Trojan asteroids and where are they? 4. What are a couple significant asteroids and what are they like? 14. Comets 1. What are recent missions to explore or investigate comets? What were they doing? 2. What causes their composition? Why are comets orbits so eccentric? 3. Why is Haley s comet important? What historical relevance does it have? 15. Telescopes 1. Choose 2 major optical telescopes. Where are they? What are their capabilities? 2. What is the VLA? What is the basic idea of aperture synthesis? 3. What are the limitations and benefits of xray, infrared, microwave, radio, and optical telescopes? 16. Mars Exploration 1. What is the scale of the history of mars exploration? 2. What are the major missions so far? 3. How were landing sites chosen? 4. How have we broken down the problem of searching for life? 17. Voyager and Outer solar system probes 1. Why were the voyager missions sent at the time they were? What were their flight paths? (find an animation) 2. What is the technology in the voyager probes like? How does it compare to current technology? 3. What is going on at the edge of the solar system? Why? 18. Our view of the universe (historically that has influenced our perspective) 1. What are the major milestones in astronomical measurements that have affected our view of the structure of the universe? 2. At each of those points, how were those new perspectives received? Did anyone know at the time? How did they react? 3. What are the outstanding questions about the universe and what are some projects that are aiming to understand the answers? 19. Galactic evolution (what changes?) 1. When were there galaxies first around? What were they like? 2. How do we classify galaxies? What is the historical origin of that classification scheme? 3. What factors influence the form of a galaxy?

4 4. What evidence supports the idea that collisions lead to different types of galaxies? 20. Spiral galaxy origins 1. What leads to the formation of spiral arms in a galaxy? How long does it take? 2. What are the different classes of spiral galaxies? What causes those differences? 3. What is the core of a spiral galaxy like and why? 21. Elliptical galaxy origins 1. What evidence supports the claim that elliptical galaxies are often formed by galactic collisions? 2. What is the core of a elliptical galaxy like and why? 3. What will the ultimate fate of an elliptical galaxy be? 22. Irregular galaxy origins and examples 1. How are irregular galaxies classified? 2. Give three examples of irregular galaxies and explanations for what lead to their formation. 23. Quasars and active galactic nuclei 1. What is a quasar and how can a black hole shoot material out? 2. What causes the formation of quasars? Will the collision of the Andromeda galaxy and our own create a quasar? What would that depend on? 3. How are quasars utilized in distance measurements? What lets us use them in that way? 24. History of universe up to first star 1. Give a detailed timeline of the history of the universe from the first millisecond up until the formation of the first star. 2. What is the importance of 3000K and why does the cosmic microwave background tell us that temperature? 25. Dark matter (nonbaryonic) 1. What is the evidence that dark matter exists? 2. What are current theories for what dark matter might be? 3. Describe how one project aims to detect dark matter. 26. Fate of universe 1. What does it mean for the expansion of the universe to be accelerating? 2. Discuss the ideas behind an open, flat, and closed universe. 3. What is the role of dark energy in describing how the universe will evolve?

5 27. Large- scale structure of the universe 1. Describe in detail the structure of the universe at the largest scales. 2. What factors affect this structure? 3. How is this structure expected to change or stay the same in the future? 28. Stellar life cycle that ends in white dwarf 1. Describe in detail the sequence of events that lead a star through its life cycle to become a white dwarf. 29. Stellar life cycle that ends in nova or supernova 1. Describe in detail the sequence of events that lead a star through its life cycle to become a neutron star or black hole. 30. HR diagrams 1. Describe the origin of the HR diagram (who developed it, why it is useful) 2. How will our sun move through this diagram? 3. What stars present challenges when classifying using HR diagrams? 31. Fusion power 1. What are the current methods used to attempt to harness fusion power? 2. What are the technical challenges that must still be overcome? 3. How is fusion power research funded? Is that funding stable? Why or why not? 32. Black holes 1. How are black holes formed? 2. Why doesn t everything in the galaxy get sucked into the black hole at the core? 3. How do black holes become active? 33. Neutron stars 1. How does a neutron star form? 2. Why doesn t a neutron star become a black hole? Can it ever? 3. Give detailed comparisons of the size, temperature, speed of rotation, density, and mass of a neutron star to other stellar materials.