[Typed answers please]

1. Write a paragraph explaining why Seasons occur on theEarth.

2. In a short paragraph, explain how Newton’s Law of Gravitydepends on mass and distance. Don’t just write the equation;explain what the equation means and give some simple numericalexamples. 3. What is mass, and how does it differ from weight?Write a paragraph.

4. List Kepler's Laws of Planetary Motion and briefly explainwhat each means.

5. In a paragraph, describe at least two of the telescopicobservations made by Galileo which supported the Sun-centricCopernican model of the Solar System.

6. What is retrograde motion of planets and how does theCopernican model of the solar system explain this apparent motion?Write a paragraph.

7. What is parallax, and why did the apparent absence of stellarparallax lead the Greeks to believe that the Earth must bestationary? Write a parargraph.

8. Write a paragraph describing the two ‘main powers’ oftelescopes. Explain why it is useful for astronomers to buildbigger and bigger telescopes.

9. What are emission and absorption line spectra? Write aparagraph explaining what they are and why they are important toastronomy.

10. Write a paragraph explaining why astronomers sometimes needto put telescopes in space in order to do their science.