Test 1 Review

Test Date: 20 October 2011, Thursday
Version: 14 October 2011 @ 3:21 am

The format of the exam will be multiple choice and short answer questions. Questions from the text and other sources are given below for your consideration as well as an old muitple choice exam. Below are some sample short answer questions to aid in your 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? Sketch a Celestial Sphere and mark the NCP, the SCP, the Celestial Equator, the Ecliptic, and the locations of the solstices and equinoxes.
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? For an observer in Eugene, OR, sketch the horizon system defining the zenith, nadir, horizon, location of the North Celestial Pole, the location of the North Star, Polaris. What is the altitude of the North Celestial Pole for an observer in Eugene, OR? What about for an observer with a given latitude? What is the maximum altitude reached by the Celestial Equator in Eugene, OR?
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? What is meant by Eclipse Seasons? Why don't eclipses occur every month?
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? Why were Helio-centric models rejected by the Greeks? How are the Greeks objections currently overcome? Compare and contrast how Ptolemy and Copernicus explained Retrograde Motion.
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. What were the roles played by Tycho Brahe, Johannes Kepler, and Isaac Newton?
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. What is the Solar Day? Contrast it to the Sidereal Day. Why is the Solar Day longer than the Sidereal Day?
14. On what day of the year are the hours of daylight the greatest for an observer in 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? What are Circumpolar Stars? 15. Why are different stars seen on the Celestial Meridian at midnight in June compared to December for an observer at a given location on the Earth?
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? WHen was annual trigonometric parallax first detected?
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. Explain the cause for the seasonal variations on the Earth. What is the Sidereal Year? What is the Tropical Year? What angle does the rotation axis of the Earth make with the normal to the ecliptic plane? What would happen to the seasonal variations on the Earth if there was no misalignment between the orbital axis and spin axis of the Earth?

22. 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