It was orbiting the dark side of Earth during the Battle of Earth, and was positioned directly between Earth and Luna. Its main purpose was to deliver supplies to the military and civilian installations encircling the globe.
The Onan's current status is unknown.
The Onan was a small, "boxy" freighter, essentially a hanging rectangular box in space without external appendages. On its interior, it was perfectly bilinear symmetrical, with two perfectly equal sides. Conveyor belts ran throughout the length of the ship, carrying metal crates that had cargo shipments. Various control panels were located along the mid-line of the vessel. It had a Shaw-Fujikawa Translight Engine.
- The Onan is the location of the Halo 2 multiplayer map Elongation.
- Despite the ship's apparent classification as a freighter, the letters "DDA" in its Hull Classification Symbol would imply it is a Destroyer. It is possible it was customized for ship-to-ship combat during the Battle of Earth, but this would not warrant a Destroyer classification. It could possibly be a ship on a ONI mission and refitted to look like a civilian craft.
- Halo 2 (First appearance)