THE SUN AND HIS FAMILY 



179 



WHAT YOU SHOULD AIM TO ACQUIRE FROM 

 THIS STUDY 



1. A knowledge of some of the more familiar constel- 

 lations and the ability to recognize them in the 

 heavens. 



2. A knowledge of what the various heavenly bodies 

 are and some of the things that science has learned 

 concerning them. 



3. Something of the tools used by the astronomer in 

 his quest of knowledge about the universe. 



TEST OF MASTERY OF THE TOPIC 



In your notebook complete the statements, answer the 

 questions, and comply with the instructions. 



1. Make a diagram showing the Great Dipper in its 

 January position and the relative positions of Cassiopeia and 

 Draco with respect to it. 



2. Show by diagrams how the principal stars in the con- 



stellations Orion, the Pleiades, Lyra, Cygnus, and Gemini 

 arrange themselves. 



3. The spectroscope enables astronomers to analyze the 

 from stars and thus learn many things about them. 



4. The astronomer's unit of measurement of distance 

 is the 



5. A nebula is . 



6. A planet is . 



7. How does a refracting telescope differ from a reflect- 

 ing telescope? 



8. The nearest fixed star is away. 



9. Stars differ from planets in that 



10. What is the Milky Way? 



11. Groups of stars that form conspicuous figures in the 

 sky are called . 



12. The speed of light is a second. 



13. The first telescope was invented by . 



14. The North Star can be located by two stars in the 



15. List the names of constellations that you are able 

 to identify in the sky. 



TOPIC 2. THE SUN AND HIS FAMILY 



SUGGESTED PROBLEMS AND QUESTIONS 



1. What heavenly bodies make up our solar sys- 

 tem? 



2. What is the nature of our sun? 



3. What has science learned of the planets? 



Distance from the sun 



Size 



Possibility of life 



Type of surface 



Length of day 



Length of year 



4. What are the characteristics of the other 

 members of our solar system? 



Asteroids 

 Comets 

 Meteors 

 Moons 



SUGGESTIONS AND HELPS FOR STUDY 



1. Most of the material of this topic is informa- 

 tional in nature and will be found in the texts and 

 special references. 



2. Problem 2 offers some interesting points for in- 

 vestigation. How large is the sun ? How far is it from 

 the earth? What are sun spots? What is found in the 

 sun? All of these questions and others should be 

 answered by your reference study. 



3. In connection with this study try to collect pic- 

 tures of the planets, the moon, comets, etc. 



4. Meteors occur in greatest numbers in August 

 about the tenth of the month, in November about the 



middle of the month, and in December about the 

 seventh of the month. Can you fin<i the reason for 

 this? 



5. You may find the following new words and 

 phrases in this study: 



asteroids relatively small pieces of matter which travel 



about the sun between the orbits of Mars and Jupiter. 

 orbit the path of a heavenly body revolving around 



another body. 

 planetoid an asteroid. 

 solar system the sun and the bodies which it holds by 



its gravitational force planets, moons, asteroids, 



meteors, comets. 

 mass the amount of matter in a body. 



INVESTIGATIONS WHICH WILL HELP ANSWER THE 

 PROBLEM QUESTIONS 1 



Experiment 119. How may sun spots be seen? 



Secure an old photographic negative or smoke a piece 

 of window glass in the flame of a candle and view the sun. 

 Often the larger sun spots may be seen in this way. They 

 will appear as dark blotches on the bright surface of the 

 sun. Record your observations in your notebook. 



Activity 120. How may the planets be distinguished 

 from the fixed stars? 



A little practice in observing will help you to recognize 

 the planets. They shine with a steady glow, and with a few 

 exceptions the ones visible are the brightest bodies in the 

 evening sky. Secure an almanac and find out which planets 

 are evening stars and which are morning stars at the time 

 when you wish to observe. Try to locate and identify some 

 of the planets. 



Record the day and hour of the observation and the name 

 and position of each planet observed. 



1 See workbook, p. 67. 



