Cimmerian System

 was a solar system with stunning colors, until the system mysteriously went dark. The system was so named by Throxillian explorers who were mystified by a system with a dark sun.

The Eighth Doctor and Charlotte Pollard visited the planet Cimmeria IV and discovered that the Cimmerians had blacked out the sun in an attempt to hide themselves from the Solarians. (BFA: Embrace the Darkness)