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The LDSS Nauvoo, later known as OPAS Behemoth and then Medina Station, is a generation ship constructed at Tycho Station. Cylindrical in shape, it measured just over two kilometers long and half a kilometer wide. Four Donnager-class battleships would fit in her belly and not touch the walls.

It was intended to be populated by thousands of Mormons and travel beyond the Sol system to Tau Ceti. However, before its voyage, the ship was used by members of the Outer Planets Alliance to attempt to divert the course of Eros during the Eros incident. The attempt failed and the ship was salvaged by Drummer, rechristened as the OPAS Behemoth. It later underwent refurbishment to transform it from a generational travel ship, into a functional battleship that would be on par with those of the Martian Congressional Republic Navy and United Nations Navy.


The command and control at the top of the ship and the main engines and the associated parts of engineering at the bottom could almost have belonged to a standard craft connected by a pair of kilometers-long shafts, one for a keel elevator to move people and another that gave access to the skin of the drum. The secondary car, stored on the exterior, could hold a dozen people. Everything else was built to spin. Ten levels of environmental engineering, crew quarters, temple rooms, schools, wastewater treatment, machine shops, and forges, and at the center, the vast interior. The Journey to Tau Ceti is specifically mentioned to be about a hundred years. Considering that the distance to the star is about 12ly, this puts its planned cruise velocity at 0.12c, and thus its total Delta-V at around 0.24c.

The vessel measures 2,460 meters long, with a width of 960 meters. Naomi Nagata at one point describes it as "a hundred million tons of steel", so its dry mass is likely in that range. While generally crewed by approximately 4,000 people, the vessel routinely carries up to 7,000 along with space for eight medium-sized spacecraft in the docking area as well as 370 Tycho Manufacturing Accelerator Tugs, permanently attached as reaction-control-system units following its recovery after the Eros incident. The Nauvoo can additionally carry numerous probes, dozens of scout and passenger skiffs, and torpedo-loading drones.

The Nauvoo is propelled by eight Tycho EDT G-4000 Series Epstein Drives, each the size of a frigate-grade warship alone, designed for interstellar travel.


Following its conversion to the OPAS Behemoth, the Nauvoo was outfitted with many various weapon systems to serve in its role as flagship of the Belt. Despite this weapons complement, the vessel was often considered a paper tiger, as firing one of the railguns would have likely ripped the ship apart due to the structure not being designed for military action. During the crisis at the Sol Ring Gate, the act of firing a torpedo caused the ship's power grid to fail, further demonstrating the ineffectiveness of the vessel as a warship. Due to the lack of any internal mechanism to support reloading the torpedo tubes, the vessel employs automated drones to manually load new missiles into each torpedo tube.

  • 6x Zakosetara-Series Heavy Railguns mounted on the bow
  • 6x external missile launchers (each loading seven single-fire torpedo tubes)
  • 170 Kess-Hashari Point-Defence Cannons

Additionally, the ship's communications laser was designed for communications across interstellar distances. As a result, the laser was easily modified to serve as a Directed Energy Weapon system.


Whilst the Nauvoo was under construction at Tycho Station, Fred Johnson used the ship's communications array to tightbeam the crew of the Tachi, who had escaped from the Donnager after an attack by unknown stealth ships.

When the protomolecule was unleashed on Eros by Protogen, Josephus Miller came up with an audacious plan to destroy the whole asteroid and station by having the OPA commandeer the Nauvoo from the Mormons and crash the massive vessel into Eros, knocking the asteroid and station out of its orbit towards the Sun. The plan ultimately failed however, when the protomolecule at the last possible moment defied the laws of physics and moved the entire asteroid out of the Nauvoo's path.

OPAS Behemoth[]

After the Eros incident, Tycho Station had to build a high speed vessel capable of catching up with the Nauvoo, so they could retrieve it safely as it was speeding out of the Sol system. Later, Fred Johnson convinced Drummer to lead a fleet to recover the Nauvoo and convert it into a warship for the Belt. An agreement was made between Fred Johnson's and Anderson Dawes' OPA factions to jointly crew the newly christened dreadnought OPAS Behemoth. Drummer becomes the ship's captain and Naomi Nagata joins her as chief engineer. Later Dawes's men arrive and are led by Klaes Ashford, who also brings Diogo Harari.

When the UNN ship Seung Un explodes, a message appearing to be from the Rocinante of James Holden claiming responsibility for the explosion for the Belt, the command crew of the Behemoth realizes that the UNN will blame them as part of the bombing. To prove that the OPA was not responsible, Captain Camina Drummer orders the ship to fire a missile on the Rocinante. The missile is fired, however this causes a power outage on the Dreadnought. Ultimately the Rocinante would escape the missile by entering the Sol Ring into the "slow zone". When the MCRN Xuesen enters after them, the Behemoth with it's OPA fleet enters the "slow zone" also.

Whilst in the Ring space, moving towards the station at its center, the speed limit in the zone is drastically reduced causing many deaths and injuries across all ships. During this, the Captain and XO were trapped by machinery, however by forcing the machinery to crush herself, Drummer was able to get X.O. Klaes Ashford free. Ashford then called for medical assistance for Drummer, whilst now calling himself Captain in her absence.

Seeing that medical supplies were low and that many wounds would not heal in zero-G, Ashford ordered that the Behemoth's drum be spun up for the first time ever to create gravity. Despite worries that it may damage the ship, the spin was successful and crews of all ships in the ring space were invited onboard.

Fearing the ring station would destroy the Sol system based on Holden's vision, Ashford commands the coms laser to be retrofitted into a weapon to destroy the Sol Ring. After repeated attempts with the laser and a mutiny lead by Holden and Drummer, the Behemoth and all other ships shut down their drives based on Holden's plan not to pose a threat to the station. Following this, The Ring station shuts down, releases every ship, and removes the speed limit. Then the Ring space opens up 1,374 Ring gates to new systems.

Medina Station[]

Having a rotating drum and being strategically position in the Ring space, the Behemoth is retrofitted and renamed to Medina Station in order to represent the interest of the OPA. The OPAS Tynan was deployed to operate from Medina Station with Ashford commanding it. The OPA began installing Comm relays through each of the ring gates, with over one hundred installed during the conflict on Ilus IV.

During the Battle for the Sol gate, Medina station is revealed to be working with the Free Navy. The Station launches missiles within the Ring space that destroys the MCRN Sagarmatha. Which helps the Free navy take control of the Ring space and allowing the Rogue Martian fleet to make transit to the Laconia Ring.

During the First battle of Medina Station, A MCRN strike team of six ships emerges out of the Sol Ring to retake Medina Station and the Ring Space. As the fleet approaches, it orders the immediate and unconditional surrender of Medina station or they would fire upon the station. Before the Martians are able to follow through with their threats, newly installed Ring Station railguns by the Free Navy open fire upon the MCRN fleet. All MCRN ships are immediately destroyed by the railgun fire.

In the Second battle of Medina Station, the Combined fleet launches hundreds of container from the Giambattista towards the Sol Ring. When the containers, Giambattista, and Rocinante transits the Ring and move towards the Ring station, Medina station and the Ring Station railguns open fire upon the combined fleet forces. Then the Rocinante is able to reach Medina Station and fires upon station's sensors and comms relays. This prevents the Medina station from using its weaponry. As the containers launch three strike teams to take the Ring Station railguns, a Medina strike team of Free Navy forces tries to counter attack the Combined fleet forces. They are taken out by the Rocinante following disabling of the Ring Station railguns. Medina station is then taken over by the Combined fleet. The battle concludes with Marco Inaros and remaining Free Navy forces being taken out.

Following the conclusion of the Free Navy Conflict, Medina Station is taken over by the newly established Transport Union to control ship traffic through the Ring space.



  • "Nauvoo" is an allusion to Nauvoo, Illinois, one of the earlier settlements of those of the Mormon faith, after fleeing persecution from the nearby state of Missouri.
  • The patch for the LDSS Nauvoo makes a reference to a verse from The Book of Mormon, specifically the Book of Ether, Chapter 12, verse 33: "And again, I remember that thou hast said that thou hast loved the world, even unto the laying down of thy life for the world, that thou mightest take it again to prepare a place for the children of men."