Braxton

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Captain Braxton is an officer of the Federation Starfleet in the 29th century. He was known to command two Timeships: the shuttle-sized Aeon, and the starship-sized USS Relativity. He has used both of these ships to travel back in time, attempting to undo changes in the timeline and in the 2370s has encountered the crews of at least two Starfleet ships of that time: that of the USS Excalibur at least once and that of the USS Voyager at least twice. (VOY episodes: "Future's End", "Relativity";TNG novel: A Time for War, A Time for Peace)