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On September 24, 2517, upon arriving at the Eridanus system, the ship detected incoming non-UNSC craft. The Dartmouth's captain ordered Welke to contact the UNSC base at Eridanus and send an escort. As the unidentified craft approached and prepared to intercept the Dartmouth, the captain ordered Welke and McNally to help her in repelling the boarders. The three were presumably killed in the ensuing firefight.
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