From Halopedia, the Halo wiki
Johnson was the fourth captain of the Phoenix-class colony ship, UNSC Spirit of Fire, succeeding Captain Donald in 2499. Under Captain Johnson, the Spirit of Fire aided in the UNSC's interstellar expansion efforts by transporting colonists and equipment for colonization, including pre-fabricated structures such as schools and hydroponics facilities. Captain Johnson served until 2505, when his or her position was filled by Captain Roggan. By at least 2531, Donald's name and their period of service as captain were painted onto the side of the Spirit of Fire's hull.
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