Unit One Study Guide
Astronomy -- ASTR 122

The Night Sky:
  1. Be able to define the three different motions of the Earth: rotation, revolution, and precession.
  2. Know how each of the three motions of the Earth cause the apparent motions of the stars in the night sky.
  3. Describe what is meant by diurnal and seasonal motions with respect to the night sky.
  4. Recall the definition of a circumpolar star. Explain why constellations were invented by nearly all ancient civilizations.
  5. Be able to relate a star's name to its brightness and constellation, as in the star alpha-Ori.
  6. Describe the celestial coordinate system of right ascention and declination, and how it relates to the Earth's coordinate system of latitude and longitude.
  7. Explain what the ecliptic is and how the equinoxes and solstices are related to it.
  8. Describe the coordinates of altitude and azimuth, and be able to locate objects in the sky using these coordinates.
Phases of the Moon and Eclipses:
  1. Be able to identify the eight phases of the Moon given a photograph.
  2. Describe the spatial relationship between the Sun, Moon and the Earth for each of the eight phases.
  3. Know the order of the phases of the Moon.
  4. Explain the difference between the synodic period and sidereal period of revolution for the Moon around the Earth.
  5. Describe the two parts to a shadow, the umbra and the penumbra.
  6. State the conditions necessary for there to be a total solar eclipse, a partial solar eclipse, a total lunar eclipse, and a partial lunar eclipse.
  7. Know what an annular eclipse is and why they occur.
  8. Explain why there is not an eclipse during every new or full moon.
  9. Define the following terms: node, line of nodes, and eclipse season.
History of Astronomy:
  1. Contrast the geocentric and the heliocentric views of the universe.
  2. Know the assumptions that Aristotle used in developing his model of the Solar System.
  3. Explain the phenomenon of retrograde motion of a planet in the sky.
  4. Recall how Ptoleme devised a way of explaining the retrograde motion of the planets.
  5. Summarize the contributions made to astronomy by Copernicus, Brahe, Kepler, Galileo, and Newton in the 16th, 17th, and 18th centuries.
  6. Recall and be able to discuss Kepler's Three Laws of Planetary Motion.
  7. Identify the main characteristics of the elliptical motion of planets.
  8. Describe the effects of Galileo's telescopic observations on the existing view of the universe.
  9. Describe Newton's Law of Gravity.
Properties of Light:
  1. Define the terms ‘wavelength’, ‘frequency’, and ‘period’.
  2. Be able to solve for either the velocity, wavelength, or frequency given the other two.
  3. Recall the electromagnetic spectrum ordered in terms of either wavelength, frequency, or energy.
  4. Know what a photon is and be able to explain its importance to our current ideas about light.
  5. State the relationship between a photon’s energy and its frequency.
  6. Describe the phenomena of refraction and reflection.
  7. Explain the Doppler Effect and how it is used in Astronomy and other fields.
  8. Define diffraction and explain how the amount of diffraction depends upon the apature.
Production of Light:
  1. Know the three different types of light spectra and how each type is produced.
  2. Given an image of a spectrum, be able to determine whether it is a continuous, emission, or absorption spectrum.
  3. Explain how, on the atomic level, emission and absorption spectra are produced.
  4. Describe what type of information about an object can be determined by examining its spectrum.
  5. Define the Zeeman Effect and what physical property of an object can be determined from it.
Telescopes:
  1. Compare and contrast the basic types of telescope designs: refractor, and reflectors (Newtonian, Schmitt, and Schmitt-Cassegrain).
  2. Describe what affect chromatic and spherical abberations have on the final image produced by a telescope.
  3. Explain why chromatic and spherical abberations occur.
  4. Know what type of optical devices (lenses and mirrors) suffer from chromatic and spherical abberation.
  5. Show how chromatic and spherical abberations are reduced in modern optical equipment.
  6. Be able to solve for the magnification, objective focal length, or eyepiece focal length given the other two.
  7. Be able to find the difference in light gathering power (LPG) between two telescopes given the diameters of their objective lenses or mirrors.
  8. Be able to calculate the resolving power (angular resolution) of a telescope given the diameter of its objective lens or mirror.