Astro 1010 Planetary Astronomy Sample Questions for Exam 5

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1 Astro 1010 Planetary Astronomy Sample Questions for Exam 5 Chapter The Giant Red Spot on Jupiter is a) a short lived storm. b) an anticyclone high pressure storm. c) the only solid ground on the planet. d) located at the north pole of the planet. 2. The source of the magnetic fields of Jupiter and Saturn are a) currents in the molten nickel-iron outer core. b) permanent magnetization of the rocky inner core. c) air currents in the upper atmosphere. d) currents in the liquid metallic hydrogen layer. 3. At the centers of Jupiter and Saturn are a) cores of pure hydrogen. b) cores of pure helium. c) cores consisting of a mixture of hydrogen and helium. d) cores of rocky materials like iron, silicon and oxygen. 4. The atmosphere of Jupiter a) is mostly a single shade of gray with no discernable structure. b) is rather calm with very few storms of any kind. c) has jet stream winds of several hundred thousand miles per hour. d) is mostly hydrogen and helium with clouds of ammonia, ammonium hydrosulfide and water. 5. The interior structures of Jupiter and Saturn are a) a solid nickel-iron inner core, a molten nickel-iron outer core, a plastic silicate mantle and a solid silicate rock crust. b) a rocky core, a liquid helium and metallic hydrogen mantle and a gaseous atmosphere of mostly hydrogen and helium. c) a liquid metallic hydrogen inner core, a solid metallic hydrogen mantle and a gaseous atmosphere. d) a solid hydrogen inner core, a liquid hydrogen mantle and a gaseous atmosphere. 6. The bands, storms and weather in the atmospheres of Jupiter and Saturn are driven predominately by a) internal heat from the planet. b) external heat from the sun. c) tidal effects from the moons orbiting the planet. d) impacts with comets and asteroids.

2 7. The magnetosphere of Jupiter a) is very large, extending beyond the orbits of most of its moons. b) is very sensitive to changes in the solar wind, changing size by a factor of 2 in a very short time. c) rotates at the same rate as the polar regions of the surface with a period of about 9 hours and 55 minutes and 30 seconds. d) is tilted from the rotation axis by around 11 e) All of the above. 8. Which of the following statements about Saturn is false? a) The average density of Saturn is less than water. b) Saturn has much slower equatorial winds than Jupiter. c) Saturn has atmospheric zones and belts like Jupiter. d) Saturn has a strong magnetic field aligned with its rotation axis. 9. The atmosphere of Saturn is a) similar to though not as active and with less helium as that of Jupiter. b) almost exactly like Jupiter s, just as active and same composition. c) completely unlike Jupiter s, no bands, no storms and very little activity. d) extremely hot and violent with huge storms and billions of massive bolts of lightning. 10. The planets Jupiter and Saturn are composed of a) mostly carbon dioxide. b) mostly hydrogen and helium with traces of all other elements. c) mostly nitrogen and oxygen with traces of others. d) mostly methane and ammonia. e) None of the above, Jupiter and Saturn are mostly rock. 11. Which of the following statements about Uranus is false? a) The solar day on Uranus is always the same as the sidereal rotational period of the planet. b) The band structure in the atmosphere of Uranus is due more to rotational effects than solar heating. c) Since Uranus is so far away from the sun and it has no internal heat, the weather is rather calm compared to other giants planets. d) The rotation axis of Uranus is tilted from its orbital plane by almost The magnetic fields of Uranus and Neptune are a) moderately strong, at an extreme tilt angle and offset from the center of the planet. b) moderately strong and aligned perfectly with the rotation axis of the planet. c) very weak, almost non-existent. d) extremely strong and tilted from the rotation axis by a few degrees.

3 13. The atmosphere of Neptune a) is very calm with no banding and few storms. b) is very active and is driven by solar heating from the sun. c) is somewhat active and is driven by internal heat from the planet. d) is non-existent. Short Answer Questions 1. Briefly describe the Great Red Spot of Jupiter: what is it, where is it, how long has it been there and what is it doing? 2. Describe the cloud structure of Jupiter. How many layers are there and what are they composed of? What altitude are they at? 3. Briefly describe the magnetic fields of Jupiter, Saturn, Uranus and Neptune their relative strengths, tilt from the planet s rotation axis and source. 4. Describe the interior structure of Jupiter, Saturn Uranus and Neptune. What kinds of layers are there and what are they composed of? In what ways are they similar and in what ways (and why) are they different? 5. Briefly describe the weather on the planet Neptune. Why is it so different from Uranus which is closer to the sun and about the same size, mass, and composition? 6. Uranus and Neptune are often referred to as siblings or cousins. Briefly describe the similarities and differences between these two planets. Chapter The Galilean moons of Jupiter are a) Phobos and Deimos. b) Miranda, Ariel, Umbriel, Titania and Oberon. c) Io, Europa, Ganymede and Callisto. d) Mimas, Enceladus, Tethys, Dione, Rhea, Titan and Iapetus. 2. The surface of the moon Io is thought to be very young because a) there are numerous impact craters covering the surface. b) the surface has many active volcanoes and no impact craters. c) the surface is completely covered in ice. d) there is no surface, it is all gas. 3. The surface of the moon Europa is a) very smooth with few craters but with cracks and ridges similar to sea ice near the earth s north pole. b) relatively smooth with numerous active, erupting volcanoes. c) heavily cratered but with no really large craters. d) heavily cratered with numerous large rift valleys. 4. The moon Ganymede is a) the largest moon in the solar system. b) saturated with impact craters over its entire surface. c) geologically active with numerous erupting volcanoes. d) covered in a thin crust of ice overlaying a liquid water ocean.

4 5. The moon Callisto is a) the largest moon in the solar system. b) saturated with impact craters over its entire surface. c) geologically active with numerous erupting volcanoes. d) covered in a thin crust of ice overlaying a liquid water ocean. 6. The density of the Galilean moons a) is highest for the moon closest to the planet and lowest for the most distant. b) the same for all the moons, about 5500 kg /m3. c) is lowest for the closest moon and highest for the most distant moon. d) is completely unrelated to the moons distance from the planet. 7. The volcanoes of Io are a) all the same, spewing molten nickel and iron out at near light speed. b) divided into two different types: geyser like sulfur plumes and hot ultramafic lava flows. c) relatively gentle when compared to Earth s volcanoes. d) all dormant. 8. Europa is a) a geologically dead world with no type of activity for the last several billion years. b) the most geologically active body in the solar system. c) probably geologically active under the ice crust and deep ocean but not as active as Io. 9. The interior of Io is a) highly differentiated with an iron core, a molten mantle and a rocky crust. b) probably not differentiated at all with a mix of rock and ice all jumbled together. c) partially differentiated with a metal rich core, a rocky-icy mantle and a thin ice crust. d) a complete mystery to scientist as we have no scientific evidence of any kind that it has any type of structure. 10. Which of the following statements about the moon Titan is false? a) Titan has a thick atmosphere of mostly nitrogen. b) Titan is only slightly smaller than the moon Ganymede. c) The average density of Titan is the same as the Earth s moon. d) Titan has rivers and lakes of liquid hydrocarbons on its surface. 11. The mid-sized moons of Saturn a) all have densities between 1200 and 1400 kg /m3 indicating they are primarily ice with only small amounts of rock. b) all show signs of extreme volcanic activity like Io. c) mostly orbit in highly eccentric retrograde orbits. d) are all probably captured asteroids.

5 12. The major moons of Uranus are a) Io, Europa, Ganymede and Callisto. b) Triton, Nereid and Proteus. c) Miranda, Ariel, Umbriel, Titania and Oberon. d) Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion and Iapetus. 13. Triton, the largest moon of Neptune is a) the only major moon in the solar system that orbits its parent planet in a retrograde direction. b) a small moon of very low density. c) a geologically inactive body. d) the largest moon in the solar system. 14. The major moons of Neptune are a) Triton, Nereid and Proteus. b) Io, Europa, Ganymede and Callisto. c) Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion and Iapetus. d) Miranda, Ariel, Umbriel, Titania and Oberon. 15. Which of the following statements about the rings of Saturn is false? a) The rings are actually composed of thousands of closely spaced ringlets. b) The Cassini Division is a gap between the A ring and the B ring. c) The structure of the outer rings is influenced by shepherd moons. d) All of Saturn s rings are located beyond the Roche limit of the planet. 16. The rings of Saturn are a) solid disks rotating around the planet. b) composed of dust sized to car sized chunks of ice. c) a thin layer of gas orbiting the planet. d) several hundred kilometers thick even at their thinnest. 17. The rings of Uranus and Neptune were discovered by a) the Voyager spacecraft when it flew by the planets b) stellar occultation observations prior to the Voyager fly-by. c) direct observation with the Keck telescope d) None of the above, Uranus and Neptune do not have rings. Short Answer Questions 1. Briefly describe the moon Io, its location, density, activity and surface features. 2. Briefly describe the moon Europa, its location, density, activity and surface features. 3. Describe the interior structure of the four Galilean moons. What kind of evidence is there to support the various theories on their interiors? 4. Describe the Galilean moon system and why it is thought of as a mini solar system. What does this tell us about how Jupiter formed? 5. Describe the moon Titan. Where is it, how big is it, what is its atmosphere like and what are the conditions on the surface like?

6 6. Describe the mid-sized moons of Saturn. What are their names? What kinds of densities do they have? What are their general appearances? 7. Describe the rings of Saturn. What are they composed of? Why do they have the complex structure seen in them? 8. Describe the rings of Jupiter, Uranus and Neptune. What is their structure and composition? How were they discovered? Chapter Most asteroids are found in orbits a) between Mercury and Venus. b) between Earth and Mars. c) between Mars and Jupiter. d) between Uranus and Neptune. 2. Which of the following is not a type of meteorite? a) stony-irons b) irons c) stones d) carbons 3. Which of the following statements is false? a) Most asteroids are irregular shaped bodies, only a few are large enough for selfgravity to have pulled them into a spherical shape. b) Asteroids are thought to be the leftover planetesimals of the inner solar system that never formed a planet. c) There are probably over 1,000 asteroids larger than 30 kilometer. d) Only about 200 asteroids have a diameter greater than 100 kilometers. e) Almost all asteroids are metallic bodies with average densities around 5 g /cm3. 4. The most common type of meteorite find is a) an iron meteorite b) a stony-iron meteorite c) a stone meteorite d) a carbon meteorite 5. The best description of a comet is a) a rocky asteroid with a highly eccentric, long period orbit. b) a planetary sized sphere of pure water ice. c) an irregular shaped dirty snowball. d) a cloud of gas and dust with no solid nucleus.

7 6. The coma of a comet is a) large pieces of ice and rock which break off when it collides with other objects. b) mostly methane gas. c) gases formed by the evaporation of ice in the nucleus when the comet gets close to the Sun. d) the solid body of the comet. 7. Which of the following is not a source of comets. a) The Oort Cloud. b) The Kuiper Belt. c) The asteroid belt. d) All of the above are sources of comets. 8. Which of the following statement about comets is false? a) The nucleus of a comet is best described as a dirty snowball. b) The gas tail of a comet is ionized gas that is blown by the solar wind. c) The dust tail of a comet is made of rocks up to several meters across. d) Comets spend most of their time well outside the inner solar system. 9. The ion tail of a comet a) always points directly away from the sun, regardless of whether the comet is approaching the sun or receding away from the sun. b) is composed of particles of dust and ice. c) is shortest when the comet is closest to the sun. d) is unaffected by the solar wind. 10. Most meteor showers occur when a) Earth passes through the coma of a comet. b) Earth passes through the tail of a comet c) Earth passes through the debris trail left behind by a comet. d) Earth passes through the asteroid belt. 11. Which of the following statements is false? a) Large meteors have never hit the Earth and never will. b) The Tunguska event was a high altitude explosion of a small asteroid or comet over Siberia in c) Many meteor shows occur at the same time each year. d) Most meteors in a meteor shower are dust grain sized particles that burn up before reaching the ground. 12. Which of the following statements about Pluto is true? a) Pluto may have an atmosphere of nitrogen and carbon monoxide. b) Pluto has about the same density as Neptune s moon Triton. c) Pluto s summer probably coincide with its closest approach to the sun because it has such an eccentric orbit. d) All of the above are true.

8 13. The dwarf planet Pluto a) has two large moons; Phobos and Deimos. b) has no moons. c) is in synchronous rotation with its largest moon, Charon. d) has three moons; Triton, Nereid and Proteus. Short Answer Questions 1. Describe the Asteroid Belt, where is it, what are the types of asteroids in it, what is the range of sizes of the asteroids and any gaps in it. 2. Briefly describe the development of a comet as it approaches the sun. 3. Describe the Kuiper Belt, what is it, where is it and what is in it. 4. Describe the Oort Cloud, what is it, where is it and what is in it. 5. Discuss the possible fates of a comet. 6. Describe the Pluto-Charon system. What are the two objects made of? How do they orbit each other? How large are they? Why was Pluto demoted from being a planet to being a dwarf planet? 7. Describe three current dwarf planets. Where are they located? How large are they? What are they made of? Why are they classified as dwarf planets and not planets, asteroids or comets?