1. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 1 Mars Figure 1.14

2. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 2 Phases of the Moon Figure 1.15

3. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 3 Solar eclipse Figure 1.16

4. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 4 A lunar eclipse Figure 1.17

5. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 5 How we know the earth is round Figure 1.18

6. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 6 Eratosthenes’s calculation Figure 1.19

7. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 7 Relative size of the Earth and Moon Figure 1.20

8. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 8 Relative distance of the Sun and Moon Figure 1.21

9. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 9 Stellar parallax Figure 1.22

10. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 10 Geocentric model by Eudoxus Figure 1.23

11. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 11 An epicycles Figure 1.24

12. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 12 Why we see retrograde motion Figure 1.25

13. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 13 Copernicus theory of planet’s distance Figure 1.26

14. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 14 Drawing an ellipse Figure 1.27

15. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 15 Kepler’s three laws Figure 1.28

16. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 16 Venus’ cycle of phases Figure 1.29

17. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 17 Observe motion of stars

18. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 18 Finding radius of the Earth

19. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 19 Definition of angular size

20. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 20 How angular size varies with distance

21. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 21 Linear size from angular size