This week we focused on the geometry of planetary orbits. The key idea was that all planets in our solar system have an elliptical orbit. We learned how to find the eccentricity of an ellipse and that gravity is a force of attraction that is dependent on the mass of objects and the distance between them. Increasing the mass of the objects increases the force between them. Decreasing the distance between the objects also increases the force of gravity between them. This coming week, we will briefly discuss the big bang theory and our solar system. We will also discuss the Sun and how it compares to other stars in the galaxy. We will focus our attention using the Hertzsprung-Russel diagram to see how stars are classified by temperature and and light output (luminosity). Homework # 14 : Due Monday, May 18, 2009 Complete remaining questions on ellipse worksheet (Friday's handout). Review Book: read pages 233-240; do questions 15-28. Quiz on Monday.
