From the dictionary...

'''Constellation''' ''n'' A set or configuration of objects,
properties, or individuals, esp. a structurally or 
systematically related grouping.

Also known as a TradeOffSpace.

A PatternLanguage is simplified when it operates within
a single constellation of forces.  Example: 
ConcurrentProgrammingPatterns for 
SymetricSharedMememoryMultiProcessors.