Exam 1 Review

Version: January 22, 2010 @ 5:55 am
Version: January 25, 2010 @ 3:30 am, old exam key added
Version: January 28, 2010 @ 2:50 am, Topic 4 including our place in the Milky Way galaxy
Version: February 1, 2010 @ 10:24 am-- Version 1, Version 2, Version 3

The format of the exam will be multiple choice questions. Below, the questions from the text are given for your consideration as well as an old exam. There are also some short answer questions below; the short answer questions are to help you study. Topics 1, 2, 3, and 4 (parts of 4?) will be covered by Test 1.

0. Astronomy, as a field, developed because of its ability to serve as a clock. What are the various motions and their associated periods which give rise to timekeeping on the Earth? What is meant by sidereal?
1. What is the Celestial Sphere? What are the equinoxes? What are the Solstices? What is the difference between the Vernal Equinox and the Autumnal Equinox? What is the ecliptic? What is the ecliptic plane? Roughly, where is the Sun on December 21? March 21? How are the North (South) Celestial Pole related to the North (South) Pole of the Earth? What is the Celestial Equator? Is the Celestial Sphere a physical model? Why did the Greeks believe it was a physical model?
2. What (and where) is the horizon? What is the nadir? What is Meridian? In which direction does the Earth spin? What are circumpolar stars? What is the altitude of the North Celestial Pole for a given observer on the Earth? What is the angle the Celestial Equator makes with the horizon for a given observer on the Earth?
3. What is the Synodic month? How is the length of the synodic month determined? At what time will the Full Moon rise? At what time will it set?
4. What is the umbra, the penumbra of an eclipse? What is an annular eclipse? What is a Solar Eclipse? What is a Lunar Eclipse? Why do we get annular eclipses? At what phases of the Moon are Solar and Lunar eclipses expected to occur?
5. In what month is the Earth closest to the Sun in its orbit? Farthest from the Sun? At what part of its orbit is the Solar Day the longest? What is the length of the Mean Solar Day? What is the analemma?
6. What are Kepler's 3 Laws of Planetary Motion? Qualitatively, what do each of Kepler's laws tell us? What is an ellipse? How are circles and ellipses related? What is meant by eccentricity? What is meant by semi-major axis? What is meant by semi-minor axis? What is meant by sidereal oribtal period?
7. What was Tycho's most significant contribution to modern astronomy?
8. What were some significant contributions of Aristotle, Aristarchus, and Erastosthenes to astronomy?
9. Compare and contrast the models of Ptolemy (geo-centric) and Copernicus (helio-centric) for the Solar System. Which was favored by the obervations at the time?
10. How was the question of geo-centric vs. helio-centric settled? Outline the issues and the steps followed which allowed us to choose between the two models.
11. What are diurnal circles? Sketch the diurnal circles for an observer in Eugene, OR, latitude ~ 44o North. Describe the diurnal circles for an observer at the North Pole, the South Pole, the Equator.
12. What is a tidal force (differential force)? Use a diagram (and words) to explain why there would be roughly two high tides per day on an ideal Earth. If the moon is full, roughly, at what time(s) will high tide occur? What are spring tides? What are neap tides? As a result of tides, how are the rotational period of the Earth and orbital period of the Moon changing?
13. Use a diagram and words to explain why we do not have Solar and Lunar eclipses each month
14. What is the Solar Day? Contrast it to the Sidereal Day. Why is the Solar Day longer than the Sidereal Day?
15. On what day of the year are the hours of daylight the greatest for an observerin Eugene? Roughly, when is the Solar Day the longest in Eugene? On what day of the year does the Sun reach its greatest altitude above the horizon at local noon? On what day of the year does the Sun reach its lowest maximum altitude (during a day) above the horizon at local noon?
16. What are the dynamical regularities of planetary motions any theory for the origin of the Solar System must explain?
18. What is annual trigonometric parallax? What were the propsed explanations for the lack of observed annual trigonometric parallax?
19. What were the reasons Copernicus's heliocentric theory was not universally embraced?
20. Describe the Copernican explanation for retrograde motion. What the Ptolemaic explanation for retrograde motion? What are morning and evening stars? Which planets will go through a complete cycle of phases (similar to the Moon's phases)?
21. Skectch a celestial sphere. Mark and label the NCP and the SCP; the Celestial Equator; the Ecliptic and the Solstices and Equinoxes. What is the Ecliptic? What are the Zodiac constellations?
22. Aristarchus's view that the Solar System was Sun-centered (heliocentric) is supported by Newton's 2nd Law of Motion. Explain.
24. Explain the origin of the seasonal variations on the Earth. What is the Sidereal Year? What is the Tropical Year? What is precession? What are some consequences of Precession? What angle does the rotation axis of the Earth make with the normal to the ecliptic plane?

25. How the force of gravity depend on the masses of the attracting masses and the separation of the masses?

26. What is meant by center-of-mass? What significance does the center-of-mass hold for orbital motion?

27. Qualitatively, describe how orbital motion works. If the mass of the Sun were to suddenly double, would the orbital speed of the Earth need to increase or decrease to remain in its current orbit? Explain your answer.

28. What is meant by Universal Gravitation? Beyond its explanation for how the attraction between two massive bodies in our Solar System works, why is Universal Graviation so powerful?


Key:

1-10: c,e,b,e,d,c,c,b,b,d,
11-20: d,a,a,b,a,a,c,d,e,c,
21-30: d,b,d,d,b,b,a,d,d,d,
31-40: d,a,b,a,b,d,b,c,b,c,
41-50: c,c,c,c,e,d,d,b,a,b