Unit 2 Part 1 The Sun1. What are stars made of?a. Gases, primarily Hydrogen, then Helium2. What provides the energy (and so light and heat) of a star?a. Atomic energy/nuclear reactions3. how many Jupiters would fit across the Sun end-to end?a. ~ 104. How many earths would fit across Jupiter?a. ~115. How many Earths could be lined up across the Sun?a. ~1106. How many Earths would fit inside the volume of the Sun?a. ~1,000,0007. How massive is the Sun compared to Earth?a. ~300,0008. The mass ratio of the Sun to the Earth is like the mass ratio of an elephant to what?a. Tadpole.9. The surface temperature of the Sun is 16 times hotter than water's boiling point. What would be 1/16th the mass of a man?a. Cat.Unit 2 Part 1B The Sun1. What is the general result of the p-p chain?a. 4 H -> He + energy + other products2. What did Einstein show to be equivalent to energy?a. Mass3. Speaking about seeing- what part of the Sun do we see?a. Photosphere4. If nuclear reactions in the core produce harmful gamma rays, why are Earthlings notdestroyed?a. The gamma rays are converted to visible light by the time they reach the photosphere.5. What is the main requirement for a habitable zone?a. Liquid water6. What could have been habitable if the Sun had been twice as massive?a. Jupiter’s Moons7. How much longer does the Sun have to live?a. About 5.5 billion years- what is humanity going to be like?8. What fraction of the solar system's mass is in the Sun?a. About 99%9. How large is the Sun? (How many Earths would fit across? How many inside?)a. 109 Earths across, 1.3 million Earths inside10. What actually produces the energy in the Sun?a. Mass of reacting elements is larger than that of the products (some convertedto energy in the core)Unit 3 Part 2A1. To find other sunlike stars go to….a. The closest stars2. So how long would it take to get to the closest star (after the Sun) if you could go only as fast as a passenger jet?a. ~5 million years!3. how many degrees are in a circle?a. 360.4. How many arcminutes are in a degree?a. 60. 5. What is the closest stellar system to the Solar System & how far away is it?a. Alpha Centauri, ~4.3 light years away6. What happens to the parallax as a star gets farther away?a. The parallax decreases as the distance increases.7. Why does light follow the Inverse Square Law?a. Every object that emits light has some intrinsic brightness (luminosity) but its apparent brightness changes with distanceb. An object emits light in all directions around it and the light is diluted through spheres around the light sourcec. The intensity of the light drops off with the square of the distanced. The inverse square comes from the 3D nature of space around a light source8. how we do measure distances to stars?a. Parallax9. Which is closer, Menkent (.067”) or Hadar (.010”)a. Hadar10. How far away is Hadar?a. 100 pc11. What factor is not in the Drake Equation?a. Communication lag due to large distances between stars12. What does the Drake Equation estimate?a. The number of technological civilizations in the Milky Way13. The first planets ever discovered outside our Solar System werea. In orbit around a millisecond pulsar, not a normal star 14. What is not part of the radial velocity method?a. A planet passing in front of its host star15. If the radius of star A is twice the radius of star B, but both have similar temperatures, how do their luminosities compare?a. Star A is 4 times as luminous as star B.16. Consider star C, a measly 3000 K star, and star D, an impressive 9000 K star. Assuming they are about the same size, how do their luminosities compare?a. Star D is 81 times as luminous as star C.17. Have objects like Jupiter been found? How?a. Yes, hot Jupiters have been found from the radial velocity method18. What methods does "wobbling stars" refer to?a. Astrometry & radial velocity19. What method does "stars that fade" refer to?a. Transits20. What kinds of stars are being looked at to find these hiding bandits?a. Stars with large parallaxesUnit 3 Part 3 The Brightest Stars1. What is true about Antares?a. The name means “Rival of Mars.” Its about 700 times the size of the sun. Possibly egg shaped. Cooler than the sun. 2. Why does the Sun appear red at sunrise and sunset?a. light passes through more atmosphere and red gets through whereas blue scatters3. Which is not a type of gravitationally bound stellar binary?a. Apparent binaryb. (visual, eclipsing, spectroscopic and astrometric binaries exist)4. Which type of binary gives information about the star sizes in addition to the combined masses?a. eclipsing binary5. Which of the following has the largest luminosity?a. most massive Main Sequence star6. What are some true facts?a. A blue Main Sequence star has a higher luminosity than a red main sequence star. b. A B type Main Sequence star that appears 100 times brighter than another B type Main Sequence star is 10 times closec. The spectrum of a star allows us to estimate its temperatured. More massive Main Sequence stars are always both hotter and brighter than less massive Main Sequence stars7. What is the lowest rung on the astronomical distance ladder?a. the Solar System8. The following are used in determining a distance from spectroscopic parallax:a. Apparent brightness, temperature from spectrum, H-R diagram, and inverse square law9. What are the 5 main properties of stars?a. Mass, Temperature, Size, Luminosity, Age on Main Sequence10. Compared to a low mass MS star, a high mass MS star has:a. higher luminosity, shorter lifetime11. Star 1 on the MS has T = 10000 K & star 2 on the MS has T = 3000 K. How do their sizes compare?a. star 1 is 30 times bigger than star 212. Which star evolves off the MS first if all formed at once?a. O-type starUnit 3 Part 4 – Stellar Birth1. What is not true about the interstellar gas?a. it's primarily Helium2. What happens to ISM atoms as they approach a star?a. they are deflected around the star3. A large patch of darkness surrounded by many stars is probably a:a. Bok Globule4. Why does a cloud speed up once it starts to collapse?a. As particles clump together, their gravitational attraction grows5. What is the Trapezium?a. Four massive stars at the heart of the Orion Nebula whose ultraviolet light is affecting other stars forming6. What objects are sometimes called "failed stars"?a. Brown Dwarfs7. A star spends most of its lifea. As a Main Sequence star8. Why does the Main Sequence part of a star's life end?a. The Hydrogen