26 
SURVEY OF THE PROBLEM 
In the last two Chapters we permit ourselves an excursion into outer 
space and observe how the complexity of the problem grows when the 
conditions of thermodynamical equilibrium in an enclosure are gradually 
relaxed. The “outside of a star” is a problem expanding indefinitely into 
the whole subject of stellar spectroscopy and stellar observation generally. 
For the most part we pursue only those branches of the subject which 
illustrate and amplify the methods and theories used for the stellar 
interior.