|Allegiance||Neutral or Uncontrolled|
|Jump Links||Enyo, Hell's Kitchen|
Dieno is where the Terran-Kilrathi War officially began. In 2634, after five years of Kilrathi piracy, a Terran transport, the TCS Anna Magdalena, was attacked by a pair of Kilrathi starfighters while ferrying orphans to their new homes on Dieno. The transport was defenseless and thus easily destroyed, leaving no survivors. This act of terrorism finally prompted the Terran Confederation to declare war on the Kilrathi Empire.
Dieno is one of three star systems in the Vega Sector named after one of the Graeae, the Grey Sisters in Greek mythology that were featured in the story of the Perseus known for sharing one eye and one tooth among them. The system's name is misspelled in all known versions of the Vega Sector maps; it is properly spelled Deino, meaning "dread" (i.e. the dreadful anticipation of horror).