The Distances to the Heavenly Bodies 171 



each other with such high speed, yet some 80 years 

 would elapse before they would meet. 



Within your lifetime let Romulus and Remus bid 

 adieu to Neptune and set out for Alpha Centauri, the 

 star that is nearest to our solar system. Their journeys 

 made among the planets have occupied nearly 27 cen- 

 turies. 7000 times 27 centuries would be required to 

 reach -Alpha Centauri, the nearest star. Many of the 

 stars are hundreds of times as far away as Alpha 

 Centauri. Only a few of them are within 400 trillion 

 miles of the earth. Most of them are many times 

 this distance from us, but it is believed that none are so 

 far away as 1000 times this distance. 



Some problems to be explained. Riding along a 

 straight road in the country at night, did you ever 

 notice a light in some house to your right or left, and, 

 after riding for some minutes more, notice that it was 

 still in nearly the same direction? Was the house near 

 the road or far from it? Did you ever go along a 

 city street and notice when you came to a cross street 

 that the moon was right down that street ? Going on 

 another block, you saw the moon again right over 

 another cross street, and so on, block after block. 

 Was the moon following you ? What other explanation 

 can you give ? 



