Preview Review Questions

2. How big is an astronomical unit?

4. How is a light-year defined?

5. What force holds the different astronomical systems described in this section together? What other forces exist in nature?

Chapter 1 Review Questions

1. What is the celestial sphere? What are the celestial equator and the ecliptic?

2. What is the difference between rotation and revolution?

3. What is a constellation, and what is special about the zodiac constellations?

4. What causes the seasons?

5. What causes the Moon’s phases?

6. How long does it take the Moon to go through a cycle of phases?

7. What is the difference between lunar and solar eclipses?

8. Why aren’t there eclipses each month?

Chapter 2 Review Questions

1. List some observational evidence that the Earth is round.

2. What is meant by the phrase angular diameter?

3. If you triple your distance from an object, what happens to its angular size?

4. What is parallax and how is it measured?

5. Where on the celestial sphere would you look for the planets?

6. Sketch the path on the sky that a planet makes when undergoing retrograde motion.

7. Will a planet in retrograde motion rise in the east or west?

8. Contrast the geocentric and heliocentric models.

9. What are the three laws of planetary motion?

10. How does astrology differ from astronomy?

11. Describe the major astronomical contribution(s) of the following in a sentence or two for each: Eudoxus, Aristotle, Aristarchus, Eratosthenes, Ptolemy, Copernicus, Tycho, Kepler, Galileo and Newton.

Chapter 3 Review questions

1. What is meant by inertia?

2. What does Newton’s first law of motion tell you about the difference between motion in a straight line and motion along a curve?

3. Explain how inertia and gravity are both involved in an orbit.

4. How does mass differ from weight?

5. If your mass is 70 kg on Earth, what is it on the Moon?

6. What is Newton’s law of gravity?

7. How can you measure the mass of a planet by studying the motion of a moon orbiting it?

8. If you weigh 110 pounds on the Earth, do you weigh 110 pounds on the Moon? Why?

9. What does surface gravity measure?

10. What is meant by escape velocity?

Chapter 4 Review Questions

1. Why is light called electromagnetic radiation?

2. What is a photon? How fast can photons travel?

3. How are color and wavelength related? What about temperature and wavelength of a glowing body?

4. What is meant by the electromagnetic spectrum?

5. Name the regions of the electromagnetic spectrum from short to long wavelengths.

6. Describe the Kelvin Temperature scale.

7. How does the color of dense materials change with temperature? How does this relate to the idea of a blackbody?

8. What makes elements different from each other? What is the arrangement of the parts of an atom?

9. What is the difference between emission and absorption in terms of what happens to an electron in an atom?

10. What are some of the things astronomers can learn about astronomical objects from their spectra?

11. Which gases in the atmosphere absorb infrared radiation? Which gases absorb ultraviolet?

12. Explain how the Doppler shift affects waves reflected by or emitted from a moving body.

Chapter 5 Review Questions

1. What is light gathering power? How does it affect the ability to see faint objects?

2. What is the difference between a reflecting and a refracting telescope? What are some advantages of a reflecting telescope? Which type are the biggest telescopes?

3. What is resolution of a telescope? What physical process limits it?

4. How is resolution affected by the size of a telescope’s mirror or lens?

5. What is the purpose of an interferometer?

6. What is a CCD and how is it better than film?

7. Why do astronomers put X-ray observatories in space rather than just on high mountains?

8. What kinds of astronomy can be done from the ground?

9. What is meant by adaptive optics?

10. How do astronomers get to use observatories?