USS Rigel (prototype)

The USS Rigel (NX-62040, later NCC-62040) was the prototype heavy cruiser in service to the Federation Starfleet in the mid-to-late 24th century. 

By 2374 the Rigel, under the command of Captain Calath, had been assigned to the 120th Tactical Wing in order to fight during the Dominion War. Later this year, the Rigel and a contingent of vessels from the 120th were ordered to investigate the disappearance of several Federation starships, including the USS Cairo (NCC-42136), along the Romulan Neutral Zone.

After some tricky negotiations with Romulan Commander Loros of the IRW, Captain Calath managed to gain permission to take the Rigel and two other vessels into the Devron system to investigate the Cairo's disappearance. Shortly after entering the system, the Rigel, her escorts and the Chraves were pulled through a spatial anomaly into a "different realm" which was cut off from normal space-time. ("Distant Realm", "Defenders of the Realm")