AY 101-002 Spring 2009 QUIZ #4 1. The tail of a comet is directed a) behind it. b) ahead of it. C) AWAY FROM THE SUN. d) in any direction. 2. Stars like the Sun derive their energy from A) HYDROGEN FUSION. b) helium fusion. c) oxygen/hydrogen combustion. d) gravity. 3. Giant planets show rings, rather than close large moons, because of the planets' a) heat. B) TIDAL FORCES. c) chemical makeup. d) rapid rotation. 4. In the broad classification of the geological history of moons, our own Moon is a) active. b) possibly active. C) FORMERLY ACTIVE. d) inactive and always been so. 5. To measure a star's distance using parallax, we use changes in its a) luminosity. b) apparent size. c) Doppler shift. D) POSITION IN THE SKY. ASSESSMENT QUESTIONS 6. One kind of supernova explosion occurs when a giant star develops a) a violent wind. b) helium fusion. c) the helium flash. D) AN IRON-RICH CORE. 7. We know there is a massive black hole at the center of the Milky Way from a) gamma rays. b) motion of gas clouds. c) radio emission. D) MOTION OF STARS.