Meridian

Meridian was a backwater Human colony world that was glassed by the Covenant in 2551, near the conclusion of the Human-Covenant War. The planet was later reclaimed by a private corporation in order to chip away the glass and make the planet habitable again, which was accomplished by the installment of Meridian Station, a former colony ship run by an AI known as Governer Sloan, who was installed as the planet's de facto leader.

The colony was home to a Guardian, which was activated by Cortana after Sloan's defection to her faction. Despite wanting his citizens to escape alive, Cortana simply decided to murder them all, and only Fireteam Osiris escaped the planet alive.