1 of 6 3/29/2015 9:18 AM

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1 1 of 6 3/29/2015 9:18 AM 1. Based on our understanding of our own solar system, which of the following would be most surprising to observe in an extra-solar system of planets? The planets nearest to the star have a lower density than the planets farther out. Several planets show large tilts of their rotation axis compared to the plane of their orbits. All the gas giants have moons. Several planets have dense atmospheres containing carbon compounds. 2. Which of the following is not a method used by astronomers to detect and study exoplanets? Rotational mapping. Gravitational lensing. Doppler shift. Transit detection. Direct imaging. 3. The Sun, the Earth, Jupiter, and Saturn's icy moons are all very different environments. The result of each type of object forming from different interstellar clouds. But their differences are only because of where each currently is in the solar system. But all formed from the same basic group of chemicals. But their differences are because each contains very different chemicals. 4. Which of the following observations does not inform astronomers about how the Solar System must have formed. All known ages for Solar System bodies are 4.6 billion years or younger. The Solar System is flat in structure. The farther out planets take longer to complete an orbit about the Sun. The inner four planets are small and rocky, while the outer four planets are large and gaseous. 5. Thinking about the formation of the solar system, what trend in composition would you expect to see from the inside to

2 2 of 6 3/29/2015 9:18 AM the outside of the asteroid belt? Rockier asteroids progressing towards ones with more hydrogen and carbon compounds. Iron asteroids progressing more towards one with silicates. Essentially the same composition all the way through. Asteroids with hydrogen and carbon compounds, progressing towards asteroids made primarily of ice. Asteroids with hydrogen and carbon compounds, progressing towards asteroids made primarily of iron and silicates. 6. How many stars are there in our Solar System? One. Eight. Nine. A few hundred. About ten million. 7. When we see them in the night sky, which of the following objects are emitting their own light? Mars Venus The Moon The Sun All of the above 8. How many planets are there in our Solar System? Which planets have densities similar to that of the Earth's? Mars and Mercury. Jupiter and Saturn. Uranus and Neptune.

3 3 of 6 3/29/2015 9:18 AM 10. In our Solar System, an object is called a planet if It orbits the Sun. It has the round shape. It has cleared its neighborhood. All of the above. 11. What is the name of the nebula from which our Solar System was formed? Pseudo nebula Solar nebula Orion nebula Crab nebula 12. Which property of the solar nebula was the most influential in giving the planets their characteristics? Mass Pressure Volume Temperature 13. The process in which a gas cools and its molecules stick together to form liquid particles is called Condensation. Depression. Evaporation. Sublimation. 14. Which was the last part of the planet-forming process? Formation of the atmosphere of the planets. Formation of the planets' core. Formation of the planetesimals. Formation of the Sun.

4 4 of 6 3/29/2015 9:18 AM 15. Exoplanets are Another name for dwarf planets. The outer most planets in our Solar System. Minor planets in the asteroid belt. Planets around stars other than the Sun. 16. Why is it difficult to observe an exoplanet directly through a telescope? Exoplanets produce very little of their own light. Exoplanets are small compared to their parent star, so they reflect only a small portion of the star's light. Exoplanets tend to be far away from their parent stars, making it hard to get both the star and the exoplanet in the telescope's field of view. It is hard to see exoplanets against the blackness of space. 17. What is gravitational lensing? The use of small telescopes to enhance the brightness of stars. The focusing and brightening of starlight by the gravitational field of the foreground star, when there is a perfect alignment with the observer. The temporary disappearance of a star as an object passes in front of it. The use of Earth's gravity to shape lenses during grinding. 18. According to the nebular hypothesis, which of the following sequences of events are chronologically correct? Solar nebula, interstellar cloud, collisions between planetesimals, accretion, planets. Interstellar cloud, solar nebula, accretion, collisions between planetesimals, planets. Interstellar cloud, accretion, solar nebula, collisions between planetesimals, planets. Accretion, solar nebula, interstellar cloud, collisions between planets, planetesimals. 19. What conclusion can be drawn from the fact that some planets with solid surfaces and satellites have impact craters? Collisions between Solar System bodies and planetesimals were common at one time. The young planets had softer surfaces. Volcanoes were very active in the early stages of planet formation. The Sun went through several explosions, ejecting material that scarred the planets and satellites.

5 5 of 6 3/29/2015 9:18 AM 20. Why was the recent discovery that planets more massive than Jupiter orbit nearby stars in small orbits surprising? Because according to the nebular hypothesis, massive planets should only form away from their star. The density of these planets is very high. According to the nebular hypothesis, planets cannot be larger than Jupiter. The nebular hypothesis predicts that close in planets should have formed a second star. 21. Which of the following is the strongest evidence in support of the hypothesis that the solar system was formed by the collapse of a gas and dust nebula? Bode's law. Images of other stars with gas and dust disks surrounding them. The existence of large clouds. The discovery of extra-solar planets. 22. Comets are while asteroids are. Icy; rocky Large; small Rocky; icy 23. Small planets do not have significant atmospheres because their is weak. Gravity Magnetic field Internal heating 24. Astronomers estimate that the age of the solar system is about years. 4.6 million 4.6 billion 4.6 trillion 13.7 billions 25.

6 6 of 6 3/29/2015 9:18 AM Compared to the planets the planets have. Jovian; terrestrial; low density Jovian; terrestrial; high escape velocity Terrestrial; Jovian; small diameter Terrestrial; Jovian; many satellites 26. Astronomers believe that the satellites of the Jovian planets were. Formed by fission. Formed by collisions with other objects. Planetesimals orbiting the growing planet. Formed elsewhere in the Solar System and were later captured by Jupiter's gravitational pull.