STELLAR EVOLUTION. 



293 



nous only through reflected light. The stars are so distant from us 

 that any planets which may attend them are beyond the reach of the 

 most powerful telescopes. In some of the planetary and spiral nebul.Ts, 

 such as the Great Nebula in Andromeda (Fig. 1), we perhaps 



Fig. 2. 

 Star-trails photographed with two and one-half inch Portrait Lens (Ritchey). 



observe the earlier stages of the process of condensation, but no distinct 

 evidence of progressive change has yet been gathered from telescopic 

 observation. In seeking for evidence of stellar evolution, on a plan 

 comprehensive enough to include a place for every star in the heavens. 



