Basic Astronomy

1. Compare the sizes or the Earth, Sun, Milky Way Galaxy, and the Universe as a whole.

2. What does an astronomer mean by ‘the Universe’?

3. What is the scientific method, and what is the difference between Science and Religion?

4. Why do different objects such as the Sun, Moon, planets, and stars all rise in the East and set in the West?

5. Why does a day measured by the position of the Sun differ from a day measured by the position of a star? How big is the difference?

6. Is your age the same as the number of times you have orbited the Sun? Explain.

7. Why do we see different stars in Summer than in Winter?

8. Why are there seasons on the Earth?

9. What is precession, and what causes it?

10. Why don’t the seasons move around the calendar as the Earth precesses?

11. Why are there leap years?

12. Why do we see phases of the Moon when half of the Moon is always illuminated?

13. What happens during a Lunar Eclipse; during a Solar Eclipse?

14. Why don't we have Lunar and Solar Eclipses every month?

15. Give an everyday example of the use of parallax.

16. Why must the baseline be long when using parallax to measure astronomical distances?

17. What two measurements must be made to determine the diameter of an astronomical object?

18. How far would you have to travel in order for the constellations to look different?

19. If light travels at 3 10⁸ meters per second and the Sun is 1.5 10⁸ kilometers from the Earth, how long does it take light to get from the Sun to the Earth?

20. How far away is an object whose parallax is 2 seconds of arc across the Earth's orbit?

21. How big is a light year?

22. Do your think an observer on another planet might see eclipses? Why or why not?