Colony Alpha V (also called Colony 5 or Earth colony 5) was the name of an Earth colony. Prior to stardate 1533, the colony was established on the fifth planet in the Alpha system. This inhabited world was administered by a governor.
In 2266, the starship USS Enterprise set course for Colony 5, with the intention of taking Charles Evans, a young man who had been stranded on the planet Thasus for seventeen years, to be reunited with his closest living relatives there. However, when it was discovered that Charlie had dangerous psychokinetic powers, which he selfishly used without regard for the well-being of others, it became evident that it was too dangerous to take Charlie to the colony. Charlie, however, used his powers to take control of the Enterprise, wishing to arrive at the colony and unleash his powers there. Fortunately, the Thasians, who had taken care of Charlie after his parents had been killed and who had given him his powers in the first place so that he could survive, arrived while the Enterprise was en route, and took Charlie back to Thasus, where he would no longer be a danger to others. (TOS: "Charlie X")