Selkren was a city on the planet Demophon. During the Galactic Civil War it was discovered that Demophon's sun was going to supernova. The news caused Selkren to erupt into chaos. Hordes of citizens crowded onto whatever starships they could find, deserting large parts of the city in their frenzy to escape the coming disaster. A dusk-to-dawn curfew was imposed to cut down on criminal activity during this period. The sheer number of starships entering and leaving the domed city during this period caused the air to become polluted.