Review for Exam 3 Chapters 9-14

1. Review for Exam 3Chapters 9-14 PHYS 1050 May 2002 N. B. Errors in the Key of Test #2 resulted in a 4 point correction that will be applied to each student’s score for the 2nd test

2. Purpose • This document is a study guide, NOT a comprehensive list of all topics included on the exam. • The exam will cover material from both the text, class notes, and class demonstrations. • SUMMARY and REVIEW AND DISCUSSION at the end of the text chapters are also good sources of information and comprehension assessment.

3. Equations and Constants • True size  distance x angular size • diameter/(2 x distance) = angular diameter/360o • F = ma • Fgrav = Gm1m2/r2 • P2 = a3 • (M+m) P2 = a3 • circumference of circle = 2  x radius = 2  r • area of circle =  r2 • volume of sphere = 4/3  r3 • diameter = 2 x radius OR D = 2r • density = mass/volume • distance = speed x time • 3600 in a circle

4. VENUS • Appearance and motions of Venus as viewed from Earth. • Venus is an inferior planet and never moves more than 47o from the Sun. • Are phases observed (like for the Moon) ? • Why is Venus the third brightest object in the sky (after Sun and Moon)? • Review basic properties of Venus (p. 207), especially unusual properties. • Compare to Earth: mass, size, density, surface temperature, seasons, satellites,rotation rate, and orbital period. • Basic structure of atmosphere. • composition, surface density compared to Earth • nature and location of cloud layers • temperature profile, average surface temperature • Understand how the greenhouse effect has changed Venus. • Does Venus have a magnetosphere? Why or why not? • Basic large-scale topography • relatively smooth surface of mostly rolling plains. • ~8% of surface “continents” • No oceans/ice deposits. Why? • Surface structures known from radar maps. • volcanic, meteor impact craters, evidence for plate tectonics, global geologic activity. • History of exploration: spacecraft and information provided. • Compare spheres on Venus to those of other terrestrial planets and Earth’s Moon.

5. MARS • Appearance and motions of Mars as viewed from Earth. • Mars is a superior planet. How does it appear to move in the sky? • Why does Mars appear red to an Earth-bound observer? • Review basic properties of Mars (p. 225), especially unusual properties. • Compare to Earth: mass, size, density, surface temperature, seasons, satellites, rotation rate, orbital period, magnetosphere. • Atmosphere • composition, surface density compared to Earth • nature and location of cloud layers, weather, dust storms • average surface temperature (day/night) and relationship to thickness of atmosphere • Does the greenhouse effect operate in the Martian atmosphere? Explain. • Large-scale topography and surface features • N-hemisphere contrasted to S-hemisphere: craters, age, elevation, geology. • Olympus Mons, Valles Marineris, Tharsis bulge, polar ice caps. • Small-scale topographic features discovered by Mariner, Viking, Mars Global Surveyor. • impact craters with fluid ejecta, runoff and outflow channels, sand dunes • relationship to geologic properties of surface, presence of water, weather changes • Two small moons, Phobos and Deimos. Compare/contrast to Earth’s Moon. • Has evidence for life on Mars been found? Possibility of life under surface? • Compare spheres to those of other terrestrial planets and Earth’s Moon. • Exploration from space: Mariner, Viking, Mars Global Surveyor, Mars Odyssey.

6. Jupiter • Appearance of Jupiter as viewed from Earth. • Describe Jupiter’s appearance through a telescope. What are you seeing? • Which constellations does Jupiter move through? How often does it pass from one to another? • How bright is Jupiter compared to other solar system objects? • Review basic properties of Jupiter (p. 281). • Compare to Earth/Sun: mass, size, density, composition, rotation rate, orbital period, magnetosphere. • Atmosphere • Composition: atmosphere and clouds • What are the belts and zones in atmosphere? (relative temperature & elevation) • What is the Great Red Spot? • What are the ovals, barges, loops and eddies? • List three factors that contribute to atmospheric features observed. • Compare to features in Earth’s atmosphere. • Internal structure • Is there a solid surface to the planet? • Describe the inferred internal structure. • What is at the core? Site evidence for inference.

7. Jupiter (continued) • Jupiter radiates twice as much energy as it receives from the Sun. • What is the source of this “excess” heat ? • Moons • Understand the basic properties of the four, large Galilean moons. • order from planet • relative sizes and densities (compared to Earth’s Moon) • unique features • (volcanoes, sub-surface ocean, largest size, magnetic field, etc.) • Magnetosphere • Driven by rapid rotation and inferred metallic hydrogen layer near core. • Unique aurora torus associated with Moon Io. • Sea of energetic, charged particles that are hazardous to people and electronics. • Ring system • Appearance and location wrt moons. • Discovery • History of exploration: spacecraft and information provided. • In 1994, comet Shoemaker-Levy crashed into Jupiter’s atmosphere. • Only recorded occurrence of such an event.

8. Saturn • Appearance of Saturn as viewed from Earth. • Describe Saturn’s appearance through a telescope. What are you seeing? • Review basic properties of Saturn (p. 308). • Compare to Earth/Jupiter: mass, size, density, composition, rotation rate, orbital period, magnetosphere. • Atmosphere • What is the composition of the atmosphere? How does it compare to Jupiter? • Are there belts and zones in atmosphere? • What is the composition of the clouds in Saturn’s atmosphere? • What are the spots sometimes seen in the atmosphere? • Compare wind speed and structure to that of Jupiter. • Internal structure: compare to Jupiter. • Saturn radiates more energy than it receives from the Sun. • What is the source of this “excess” heat ?

9. Saturn (continued) • Rings • What are the rings? (composition, particle size, separation) • How were they discovered? • What is believed to be the origin of the rings? • What causes some of the structure observed in the rings? (e.g., Cassini Division produced by gravitational influence of small moon) • Understand meaning of “Roche limit” • Relationship to tidal forces, ring formation. • Moons • Large moon: Titan • atmosphere • possible surface material • Medium-sized moons • properties of surfaces • icy compositions • History of exploration: spacecraft and information provided.

10. Uranus • Edge of visibility without optical aid. • Who discovered Uranus? When? How? • What color does Uranus appear to be? Why is it that color? • Review basic properties of Uranus (p. 332). • Compare to Earth/Jupiter: mass, size, density, composition, rotation rate, orbital period. • Uranus’ rotation axis tilted 98o from normal to orbital plane. • How does this affect the “seasons” on Uranus? • Atmosphere • Uranus appears to bland when compared to other jovian planets. Why? • Compare its composition and clouds to Jupiter/Saturn and Neptune. • Interior Structure • Compare to Jupiter/Saturn and Neptune. • Excess energy? • Magnetic field size, orientation, generation.

11. Uranus • System of narrow, rope-like rings discovered around Uranus in 1970’s. • How were they detected? • What are they made of? • Why are they not immediately visible through a telescope, as are Saturn’s rings? • Moons • Describe the moon system about Uranus. • Are there any large moons? • How do the mid-sized moons compare to the mid-sized moons of Saturn? • History of exploration: • spacecraft and information provided.

12. Neptune • Cannot be seen without a telescope. • Who discovered Neptune? When? • Neptune’s existence was predicted, then confirmed. • Review basic properties of Neptune (p. 341). • Compare to Earth: mass, size, density, composition, rotation rate, orbital period. • Describe the appearance of Neptune by telescope and as imaged by spacecraft. • Why does Neptune appear so blue in color? • Atmosphere • Compare its composition and clouds to Jupiter/Saturn and Uranus. • Storms, zonal flow, belts and zones? • Interior Structure • Compare to Jupiter/Saturn and Uranus. • Excess energy? • Magnetic field size, orientation, generation.

13. Neptune (continued) • System of narrow rings was discovered around Neptune. • How were they detected? • What are they made of? • What is odd about their structure? • Moons • Describe the moon system about Neptune. • Are there any large moons? • Describe any unusual features or properties of these moons. • History of exploration: spacecraft and information provided.

14. Pluto • Cannot be seen without a telescope. • Who discovered Pluto? When? • Review basic properties of Pluto (p. 347). • Compare to Earth: mass, size, density, composition, rotation rate, orbital period. • Pluto’s orbit is tilted 17o to the ecliptic - largest value for any planet. • Pluto’s orbit has an eccentricity of 0.249 - largest value for any planet. • Describe the appearance of Pluto by telescope. • Atmosphere • Composition, seasonal variations • Pluto is not a jovian planet - it has a surface. • Describe current ideas describing this surface. • What is believed to be the overall composition and structure of this planet? • What object in the solar system does it most resemble? • Moon • Describe Pluto’s one large moon, Charon. • Describe the unusual characteristics of the Pluto/Charon system. • What are some theories for the formation and evolution of Pluto/Charon. • History of exploration: spacecraft and information provided.