- For other uses, see Nebula.
In the mirror universe, the ISS Nebula (NCC-62303) was a Terran starship, a Nebula-class science vessel in Starfleet service in the 2400s and 2410s decades. (STO - Cardassian Struggle missions: "Jabberwocky", "Mirror Invasion")
In 2409, this ship was part of the resurgent Terran Empire's presence in the Badlands when Captain Leeta of the ISS Fortuna and a small fleet confronted an Allied starship emerging from a temporal rift. Leeta and her fleet attempted to prevent the Allies from returning the Orb of Possibilities to Vedek Krin on Bajor but were defeated in combat and chased away. (STO - Cardassian Struggle mission: "Jabberwocky")
From that year onwards, the Nebula and other ships of its class were involved in Terran incursions into the primary universe, and could also manifest through temporal rifts opened by Tholian starships. (STO - Legacy of Romulus mission: "Azure Nebula Rescue")
The Nebula was part of the Terran fleet ransacking Vauthil Station, a starbase of the Reman Resistance and, later, the Romulan Republic. The Terran forces were repeatedly pushed back to their own realm by the Reman's allies, and by 2410, the Alpha Quadrant Alliance. (STO - Legacy of Romulus mission: "Mirror Invasion")
When Pah-wraith-infused Admiral Leeta launched another invasion on Deep Space 9, the ISS Nebula was part of her fleet. The fleet operated from Terok Nor, which Leeta brought across. In this battle, the Terran forces were supplemented by ships from the 29th century. With too many ships lost, Leeta pulled Terok Nor back into her own universe and vowed to return. (STO - Agents of Yesterday mission: "Counterpoint")
In 2410, Admiral Leeta coordinated an invasion through the Badlands from the ISS Enterprise-F, bringing three Terran starbases and hundreds of ships across. On the Alliance side, Commander Mesi Achebe led the defense efforts from the USS Malinche. For this mission, the Terran Nebula-class science vessels had been fitted with powerful tractor-beam repulsors, so they could push Alliance ships away from moving satellites and prevent these from being reprogrammed against the Terrans. The Allies crippled each station and forced the Terrans to retreat when the Enterprise-F suffered too much damage. (STO - Victory is Life mission: "Badlands Battlezone")