From Halopedia, the Halo wiki
The Argosy is considered streamlined, sleek, and clean. It was armed with weaponry and had communications beacons along its front.
The Argosy was in the same orbital area to the UNSC Spirit of Fire. When Professor Ellen Anders was transferred to the Spirit, initially believed the Argosy was the Spirit of Fire and that the Spirit was a space station.
The Argosy is named for a term referring to a merchant vessel or a fleet of such vessels.
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