Vega IX

From Memory Alpha, the free Star Trek reference.

You may also be looking for the Vega Nine probe.

Vega IX is a planet in or near Federation space, in the Vega system.

In the mirror universe, Vega IX was the location of a Terran colony, where Terran Empire captain James Kirk executed over 5,000 colonists in his second action as commanding officer of the ISS Enterprise. (TOS: "Mirror, Mirror")

[edit] Background

It is not clear if Vega IX is the location of a Human colony in the more familiar Federation universe. However, there have been numerous references to Vega colony, so it seems a likely conclusion that the colony could lie on this world in this universe as well, since we at least know there is a colony in the same system here.