200 Trees, Stars, and Birds 



Orion, you will see that Capella is midway between the 

 belt of Orion and the North Star. It gives out 120 

 times as much light as the sun. In other words, 120 suns 

 at the distance of Capella would give us no more light 

 than we receive from Capella. As its color is like that 

 of the sun, it is probably of about the same temperature, 

 and in order to give out so much more light it must be 

 many times as large as the sun. Capella is far enough 

 north to be above the horizon most of the time, but in 

 August and September, when Vega is almost overhead, 

 Capella is very low and not visible from the Southern 

 states until late in the evening. What effect would it 

 have on us if this star were to come within 100 million 

 miles of the earth? 



Bootes. Following the curve of the Big Dipper 

 handle, a line extended about 30 degrees farther will 

 come to Arcturus, a bright star with a reddish tinge. 

 It is in the constellation Bootes, the Herdsman, and is 

 one of the four brightest stars we can ever see in this 

 latitude, the others being Sirius, Vega, and Capella. 

 Arcturus is mentioned in the book of Job, but not until 

 recent years has much been known about it or about 

 any of the stars. Arcturus is much brighter than the 

 North Star, although it is probably little, if any, 

 nearer to us. Some astronomers think it is more 

 than twice as distant as the North Star. It is mov- 

 ing through space many miles a second and coming 

 several miles nearer to us each second. Within your 

 lifetime you will not detect any change in its place 

 among the stars, but since its position was deter- 

 mined by the Egyptian astronomer, Ptolemy, in the 



