The USS Sojourner (NCC-78561) was a Galaxy-class Federation starship, launched in 2380. Under the command of Captain Owen Cavanaugh, she embarked on a long-range exploration mission of the rimward Beta Quadrant. During this period, Dr. Saelyn was the Sojourner's chief medical officer, and Dr. Baxa was the ship's counselor.
In 2385 (in the Pendragon timeline), the Sojourner discovered a repository of Iconian and Tkon artifacts, as well as a Preserver obelisk. Shortly afterwards, Captain Cavanaugh relayed his science officer's logs to Starfleet, and also to his friend, Timothy Sinclair. (Star Trek: Pendragon: "Land of My Sojourn")