(Write your answers on a separate sheet of paper.)

Historical Figures of Astronomy

Matching: Match the historical figure with his contribution to the evolution of astronomy as a science. (Note: choices may be used more than once)

a. Copernicus b. Aristotle c. Kepler d. Plato e. Galileo f. Ptolemy g. Eratosthenes h. Tycho i. Philolaus

1. Developed an astronomical model that contained 55 spheres turning at different rates and at different angles to carry the seven known planets across the sky

2. Believed Earth moved around a central fire

3. Discovered four moons circling Jupiter

4. Determined that the orbits of the planets around the sun are ellipses with the sun at one focus

5. Calculated Earth's radius by utilizing the position of the sun in Alexandria and Syrene and the distance between the two cities

6. Believed that the heavens are perfect and must be made up of perfect spheres rotating at constant rates and carrying objects in a circle

7. Proved Ptolemaic theory was invalid because he found no parallax with the discovery of a new star

8. Believed the sizes of the celestial spheres carrying the outer three planets are determined by spacers consisting of two of the five regular solids

9. Developed a heliocentric Universe model with retrograde planetary motion

10. Reported that the Milky Way was made up of many stars too faint to see with the naked eye.

11. Explained planetary motion by describing epicycles, deferents and equants

12. Believed that the Universe was divided into two parts: Earth, imperfect and changeable; and the heavens, perfect and unchanging, a geocentric model used for over 2000 years