List of unnamed Federation starships of the Prometheus-class.
Escort for USS Voyager
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A Prometheus -class (middle right) escorts USS Voyager
In 2378, an unnamed Prometheus-class starship stationed near the Sol system was dispatched by Admiral Owen Paris to a defensive point near an opening Borg transwarp aperture near Earth.
The ship opened fire on the emerging Borg sphere, and assisted in its destruction. Following the emergence of USS Voyager from the debris, the unnamed Prometheus-class starship assisted in escorting Voyager back to Earth. (VOY: "Endgame")
Battle of Procyon V
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An unnamed Prometheus-class ship
In an alternate timeline, occurring during the 26th century, an unnamed Prometheus-class starship participated in the Battle of Procyon V assisting the Federation in defeating the Sphere-Builders. (ENT: "Azati Prime")