From Halopedia, the Halo wiki
Project Archeon was a United Nations Space Command initiative whose goal was the interrogation and study of the archeon-class ancilla, Intrepid Eye. The Forerunner intelligence was recovered by the UNSC on the Outer Colony world of Gao in July of 2553 and subseqently taken to the recently-commissioned Argent Moon, an ONI research and development station hidden in the Crow's Eye Nebula. There, Intrepid Eye was kept under heavy guard.
On March 3, 2557 an accident aboard Argent Moon resulted in the release of asteroidea merozoite throughout its ventilation system, killing everyone aboard by March 17. Then, on October 23, 2558, the station was destroyed at the hands of the Spartan-IIs of Blue Team.
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