Iridin
Iridin was a Federation border colony in the Alpha Quadrant. 

During the  of 2256, on or around stardate 4851.5, the Klingons launched an attack at the research outpost located in this colony. The children who were spared found themselves as orphans. ()

In 2259, the location of this colony was labeled on a stellar cartography chart that was seen on the 's ready room viewscreen. This colony's symbol had a blue color, indicating that it was affiliated with the . () 

In 2399, the location of Iridin was labeled in a Federation star chart that was in Fleet Admiral Kirsten Clancy's office at Starfleet Headquarters. () 

In 3189, the location of Iridin was denoted on a holographic star chart of the galaxy at Federation Headquarters. ()

Colonies