From Halopedia, the Halo wiki
In March 2553, during the Blooding Years, Austen manned the weapons controls. When the Infinity was given permission to fire on the Defender of Faith he was ordered to use Howler missiles to destroy the ship. Using pods 1-3 damaged the Covenant destroyer, and pods 4 and 5 destroyed the ship. Six months after the Ur-Didact's attack on Earth, Lt. Austen was still manning the weapons systems. After Captain Thomas Lasky gave the order, Infinity's sub-vessels were released on Austen's mark. He then transmitted target data to the leaders.
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