The UNSC Magellan was a UNSC Carrier.

In 2517, Jacob Keyes was assigned to the Magellan as his first assignment prior to graduating Luna OCS Academy. Those orders were rescended when he was sent to help Dr. Catherine Halsey study the Spartan Children.[1]

Some time between 2525 and 2531, the Magellan's Shaw-Fujikawa Slipspace Drive was damaged and needed to be repaired. The procedure was extremely dangerous, because such drives aren't meant to be taken apart once they go active. Spartan-104 witnessed the repair [2].

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