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This page is about the Tv icon.png TV location. For the books incarnation, see Slow zone (Books).
Book-icon-simple.png Books location Tv icon.png TV location

The Ring Space (also known as the Slow Zone) is the bubble of space discovered after transiting through the Ring, the stationary structure created by the protomolecule 2 AU outside of Uranus' orbit after it left Venus.


It is depicted as a starless and seemingly empty alien nebula. At the time of its first discovery, no electromagnetic transmissions were detected traveling between the Slow Zone and the Sol system. In the Ring Space, there appears to be a large structure referred to by The Investigator as "the nucleus," otherwise known as the Ring Station.


Main article: Slow zone incident (TV)

The Rocinante was the first manned spacecraft to safely enter the Slow Zone without fatalities after The Investigator warned Captain James Holden; "Come in too fast, the room eats you". Previously, the ill-fated Y Que attempted the same feat and the pilot, Belter Manéo Jung-Espinoza, was killed after the Slow Zone stopped his ship but his body continued forward.

At the time of discovery of the Ring Space, it was determined the speed limit was 18,000 km/h (5000 m/s). Following the detonation of a grenade during the Slow Zone Incident, the speed limit was later reduced to 28.997m/s, causing all vessels in the area to undergo massive (507 G) deceleration and killing several thousand people. Eventually, the speed limit was lifted completely and the other Ring Gates were activated after the crew of the Rocinante (along with the unexpected assistance of Clarissa Mao/Melba Koh, Anna Volovodov, and Bobbie Draper) prevented the permanent destruction of the Ring (and, by extension, the possible extinction of all of humanity) and showed the Ring Station that humanity was not a threat.

Following the Slow Zone Incident, the joint UNN/MCRN/OPAN fleets retreated from the Ring Space except the OPAS Behemoth which was repurposed as a permanent space station to remain inside the space, referred to as Medina Station. Camina Drummer assumed control over the station as OPA Station Commander, aided by Commander Klaes Ashford.

The disappearance of multiple colony ships awaiting passage at the Sol gate as apparent victims of piracy led to the United Nations Navy relocating the UNN Tripoli, part of the EMC ring gate fleet, to the Ring Space indefinitely until the issue would be resolved. Medina Station protested that notion however.

With the onset of the Free Navy Conflict, the Tripoli had resumed its position outside the Ring Space. Following the Battle for the Sol gate, its victory made possible in part by Medina Station supporting the attacking forces, the rogue MCRN fleet transited the ring and passed through the space en route to the Laconia system. The Barkeith was lost in transit to Laconia however due to a ring network anomaly.

Cooperation between the MCRN defectors and Free Navy Medina Station resulted in the construction of the Ring Station railgun turrets to exert control over the entire Ring Space and all connected systems to it.

Main article: First Battle of Medina Station (TV)

Following the Ceres Offensive, a MCRN task force comprised of Scirocco-class assault cruisers, heavy frigates and Morrigan-class patrol destroyers under the command of Admiral Sandrine Kirino attempted to invade Medina Station and take back the Ring Space from the Free Navy. After destroying the sentry ships at the Sol gate, the flotilla moved into the Ring Space with Medina Station target locked and given an ultimatum. The sudden deployment of the Ring Station railguns destroyed all six vessels while approaching the station, killing Kirino in the process.



  • The Ring Space as depicted in the TV series differs slightly from its depiction in the books. The books describe the Ring Space as The Slow Zone, a term coined by Holden in a broadcast made by him after the Rocinante's initial crossing in Abaddon's Gate. The second major difference is that while the TV series depicts Ring Space as something akin to the interior of a glowing blue sphere, The books describes it as pitch black with no stars or light emitting objects occupying the space, something that our protagonists find mildly disturbing.
  • The books also go into detail regarding the size of the Ring Space, describing the sphere made by the Ring Network and Ring Station as being a little smaller the diameter of the sun. In Persepolis Rising it's made clear that while the Ring Network and Ring station form a sphere of roughly one million kilometers in diameter, the size of space it occupies is thought to be infinite. It's also mentioned that as far as human scientists can tell, The Ring Space is the most energetic place in the universe.
  • In Persepolis Rising the Ring Station at the Center of the Ring Space hosts 3 large railguns installed by The Trade Union in order to defend the space and Medina Station. Curiously, the firing of the railguns doesn't seem to cause the any measurable recoil to be imparted on the Ring Station to which they're attached, seemingly in violation of Newton's Third Law. It's theorized that when the railguns fire, the recoil does indeed cause movement but not just of the Ring Station but rather the whole Ring Network, moving it in its entirety through the infinite Ring Space, and as there are no celestial bodies to measure that movement against, it simply goes unnoticed by its occupants.
  • It's said the Cosmic Microwave Background radiation within the Slow Zone is older than the universe itself.

See also[]