The Starry Heavens 181 



How TO USE THE STAR MAPS 



IT will be an easy matter to find on the maps the stars 

 and constellations mentioned in the text. To locate them 

 in the heavens is much more important and interesting. To 

 do this, turn to the map that shows the appearance of the 

 heavens at the season when you are making the observations. 

 If the date or hour differs a little from those given at the 

 bottom of the map, the position of the stars also will differ 

 a little. Holding the map high in front of you, notice that 

 the word "Zenith" indicates the place in the heavens that 

 is directly over your head. Near this you will see, if the 

 sky is clear, the constellations shown near the word " Zenith" 

 on the map. Down near the horizon you will see those shown 

 near the bottom of the map. Those toward the right side of 

 the map will appear in the heavens somewhat to your right 

 and those toward the left of the map in the corresponding 

 position in the heavens. In using a map under which is 

 printed "Looking South," remember that east is toward 

 your left hand and west toward your right hand. The lines 

 connecting stars on the map have no counterparts in the 

 heavens, but they will make it easier for you to find the stars. 

 If the map is held directly over the head, the stars on it will 

 appear as they do in the heavens. 



From hour to hour and from night to night the stars change 

 their positions with reference to things on the earth, because 

 of the motion of the earth itself. You should become 

 accustomed to locating the constellations not with reference 

 to anything on the earth, but with reference to other con- 

 stellations, and to recognizing them by the arrangements of 

 stars in them. However, in pointing out a star to another 

 person, it is well to stand in such a position that the star 

 appears to be directly over a telephone pole or some other 

 near object which is unmistakable. If the other person gets 

 in line with you and the pole, he can tell what star you mean, 

 if you make clear to him how high he should look. 



