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Galaxies and Quasars
       
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 Galaxy Properties 
 
 
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Parts of Galaxies
       
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Stellar
Populations
 
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Optical   
       
       
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Ultraviolet 
 
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X-Rays 
 
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Gamma
Rays 
 
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Infrared  
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Radio, mm and sub-mm 
 
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Spectroscopy 
 
 
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Atoms and
Molecules 
 
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 Pairs, Groups and
Clusters 
 
 
 
  
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  Intergalactic,
Intracluster 
 
   
  
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Distances & Large Scale Structure 
 
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Cosmology  
 
 
       
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