﻿158 
  

  

  ANNUAL 
  IlEPOET 
  SMITHSONIAN 
  INSTITUTION, 
  1921 
  

  

  cumstances 
  of 
  exalted 
  temqyerature 
  and 
  fvemure 
  lyrevailing 
  within 
  

   stars^ 
  unio7i 
  of 
  tJiese 
  electric 
  partides 
  niiay 
  occur^ 
  with 
  annihilation 
  of 
  

   mass 
  and 
  liberation 
  of 
  energy. 
  If 
  so, 
  a 
  source 
  adequate 
  to 
  swpyly 
  

   stellar 
  energy 
  for 
  iTmn&nse 
  periods 
  of 
  time 
  is 
  available. 
  

  

  

  Fig. 
  3. 
  — 
  The 
  temperatures 
  of 
  the 
  stars 
  estimated 
  by 
  comparing 
  their 
  spectral-energy 
  

   curves 
  with 
  those 
  of 
  the 
  perfect 
  radiator 
  

  

  From 
  the 
  known 
  mass 
  of 
  the 
  sun 
  it 
  is 
  computed 
  that 
  if 
  it 
  were 
  

   completely 
  annihilated 
  with 
  evolution 
  of 
  energy, 
  the 
  supply 
  would 
  

   suffice 
  to 
  mmntcdn 
  the 
  present 
  rate 
  of 
  solar 
  radiation 
  about 
  fifteen 
  

   trillion 
  yearn. 
  So 
  the 
  present 
  view 
  ascribes 
  enormous 
  ages 
  to 
  the 
  

   stars, 
  abundantly 
  sufficient 
  to 
  satisfy 
  the 
  most 
  extravagant 
  time 
  

  

  