A Starfleet ship also stranded in the Delta Quadrant.
The USS Equinox was a Nova-class science vessel, a small starship designed for research and exploration. She was caught in the Delta Quadrant by the same forces that stranded Voyager and was left far from home with a crew who had to survive in an unfamiliar region of space.
Captain Rudy Ransom commanded the ship, and the crew found themselves in an increasingly desperate situation. In order to speed up their way home, they turned to killing a group of alien lifeforms and using them as an energy source. This breached Starfleet principles and set the Equinox against the USS Voyager when Captain Janeway discovered what they were doing. Several members of the Equinox crew sided with Ransom, while others began to question the choices they had made.
The confrontation between the two Starfleet ships ended with the loss of the Equinox after a damaging fight with the aliens, and a few survivors joined Voyager. The story was a bleak look at how far Starfleet officers might go when pushed, and it gave Captain Janeway one of her strongest tests as a leader.