Sidonia no Kishi Wiki


Sidonia (シドニア) is a massive interstellar seed ship and Guardian carrier. The title of the series is named after this very ship, which is the last known remnant of humanity.

The intergalactic space ship, Sidonia. This is the transport ship that protects both humanity and human culture.

Description & Characteristics

Flag of Sidonia

Both an interstellar seed and carrier warship, Sidonia is one of the many seed carrier ships that houses the surviving remains of humanity after the destruction of Earth by the Gauna. In an elongated octagonal shape, seemingly built right out of an asteroid, it has two massive boosters on the rear as its propulsion. However, since there's minimal spacial resistance for movement, the ship mostly relies on inertial drift for travel. Suggestively, Sidonia doesn't have any advanced FTL (Faster Than Light) capabilities.

Within the ship, Sidonia is a limited self-sustainable colony. Even though the colony is self-sustainable at extended periods, they are not unlimited in resources in food and materials. To remedy human food consumption, scientists modified every citizen to be capable of photosynthesis to limit their need for food. The ship also seems to run on what is called "Organic Converter Reactors", where they send people who have reached an age limit of some sort to die and become fuel for the ship. It is also believed that the organic material is also partially used for the production of food. These machines are allegedly extremely complex, and it is almost impossible to find someone hiding within one. When resources are low, Guardians also double as advanced scouts and retrieval units for mining water and raw materials for maintaining and constructing for Sidonia.

Adapting a Japanese culture, the ship evolved their own culture from it and has since created a host of new kinds of humans. They have since created a hermaphroditic type of humans, called the third gender, which allows the person to change into one of the two primary genders after choosing a mate. They have also utilized cross-hybridization, crossing animal DNA to create animal-humanoids and even used Gauna DNA to create hybrids to fight for their cause. Cloning and advanced methods of aging and compressed education are used to maintain Sidonia's population and also keep a steady supply of Guardian pilots.

Although not all citizens are chosen for being a Guardian pilot, many young teens are chosen or choose to become Guardian pilots. Since the Gauna threat has lasted for many generations, massive fatalities are common and society within Sidonia encouraged a warrior culture to produce as many talented pilots as possible to anticipate the next Gauna attack. Although the combined resources of Sidonia are able to defend itself from the Gauna, the price is often high and there's yet to be a weapon(s) and/or method(s) of defense that can effectively minimize the fatality rate during wartime.

For combat, the ship itself has forward and rear cannons for long-ranged combat. However, it relies heavily on its squadrons of Guardians to protect itself and its inhabitants. Launched from the forward section of Sidonia, there are a series of launch tubes that can sortie hundreds of Guardians to defend itself from the Gauna and other threats. However, despite being centuries old, the inhabitants never tried to upgrade the combat capabilities of Sidonia to better defend itself from future attacks. Instead, the colony inside developed more advanced Guardians to compensate against future threats. However, after encountering massive amounts of Gauna after the 100 year peace period, Sidonia was rapidly upgraded.

Sidonia increased Research & Development to develop its military capabilities. Dispatching its Guardian fleet to retrieve resources, they developed and upgraded a series of armored plating, sensors, and weaponry to Sidonia to better protect themselves from future threats. In addition, Sidonia's engineers developed advanced support units for future incursions such as the recent Type 19 Guardian as well as the Mizuki-class starship. Overall, the Sidonia is an incredibly formidable ship, capable of sustaining a population of half-a-million humans while simultaneously fending off Gauna.


The Sidonia is well armed and armored. Designed to resist the Gauna and survive deep space for long periods of time, she utilizes immensely thick armor and structure to protect her passengers. She also contains a diverse number of weapons systems.

Guardians are the main defensive and offensive armament of Sidonia. Repeatedly improved upon and adapted by Sidonia's engineering teams, they are on Type 17 by the time of the slaughter of 99% of the population, and are on Type 18 by the beginning of the story. Guardians can fly at colossal speeds and can multiply their speed by gathering in a clasp formation. By linking their Heigus engines together, they can reach significant fractions of the speed of light, as shown when Sidonia is engaging the Gauna around the Lem system. Guardians contain a Heigus cannon for long-range combat, utilizing Heigus Particles to create an energy beam that is powerful enough to strip Placenta off a Gauna.
  • Heavy Mass Cannon
The Heavy Mass Cannon is one of Sidonia's primary armaments. Nestled along the hull of the Sidonia, aimable and massive, it fires chunks of mass at immense speed, using kinetic energy and inertia to inflict damage. The Heavy Mass Cannon most likely operates as an electro-magnetic railgun, firing a large chunk of iron at the target, though this is not explicitly stated in the manga.
  • Anti-Planet Missiles

Anti-planet Missile.png

An uncommonly destructive missile used by Sidonia to destroy large objects, from asteroid to planet-sized. First used against a gas giant that was harboring Gauna, they are used again to destroy an asteroid on a collision path with Sidonia.
  • Main Railgun


The large railgun that spans throughout Sidonia is the largest in their arsenal. Spanning 28 kilometers, the barrel (which most likely resides inside the residential area) goes all the way down to the engine room and all the way up to the ocean level. When firing, serious recoil is inevitable. During the first shot in the storyline, Sidonia would have been unable to recover if it did not balance against Lem-IX. However, due to recoil, Sidonia was caught in the planet's gravity.


Sidonia carrier.jpg

A cross-section of Sidonia

Sidonia is built as a giant shaft, designed with the gravity well being "down" towards the engines. Approximately five kilometers wide and 29 kilometers long, she contains all of the elements needed for life: an enormous ocean layer for ocean life, including edible fish; a massive residential area in the middle of the ship; a built-in asteroid for continuous harvest of raw materials; and a thick (500m+ in places) layer of ice surrounding the ship.

Armories, factories, and industrial sections are located in Sidonia's ice layer. Sidonia was also built through an asteroid, giving the crew a ready source of raw materials. Even so, they must occasionally harvest ice from minor asteroids and planetoids to replenish water lost through its centuries of service.

A "gravity generation device" is located just above the engines. This device generates gravity through an unknown method.

The front of Sidonia contains two enormous front jets, used to retrofire and slow down the ship. They are only used once, to decelerate into Lem IX orbit. In the residential area, a public warning is issued whenever these are engaged.


Sidonia left the Solar System on 2 August 2384.

In 2513 AD, the closest ship to the Sidonia, the Aposimz, sent out a final transmission. 178 years later, in 2691, Sidonia received this message. It was the last message Sidonia received from another seed ship. Approximately 700 years had gone by since Sidonia heard from another Seed Ship.

Sidonia has traveled the void of space for over a thousand years. During that time, Sidonia has encountered a number of strange planets and artifacts. Approximately 400 years after she left the Solar System, in 2784, Sidonia encountered an alien artifact that contained, in addition to a Gauna, a number of pieces of material which formed the Kabizashi. Sidonia is the only known ship to have discovered a way to destroy the Gauna's True Body.

Sidonia firing the main railgun.

100 years ago, the scientist Ochiai accidentally disabled Sidonia's security systems and let in two Gauna. In the few minutes between the Guardians destroying the Gauna and the Gauna entering Sidonia, 99% of the crew had been killed. The majority of the contemporary crew are clones or descended from clones, either from the surviving colonists or DNA stored in Sidonia.

At the time of the story, Sidonia has reached the first named star system, Lem. The Lem star system has several exoplanets, including one in its circumstellar habitable zone.

As a Seed Ship, Sidonia long since adopted the rule that if a habitable exoplanet was discovered, 50,000 settlers would be left to colonize the planet. Sidonia's primary mission was to colonize planets and ensure the continuation of the human race, not to defeat the Gauna. Defeating the Gauna becomes a method to ensure that mankind's new home does not suffer the same fate as Earth.


Due to the nigh-complete lack of communication with other seed ships, Sidonia has evolved into an entirely unique society with equally unique technology. The evolution of their technology has followed rather unsurprising directions given their desperate situation for survival.

Resource Extraction and Preservation

Sidonians are experts at resource extraction and preservation. They genetically engineered their entire population to be able to use plant-like photosynthesis to generate nutrients for their bodies, reducing their need to eat food down to roughly one meal a week. They do still need to drink water regularly but Sidonians have also developed extremely advanced filtration technology, able to extract clean drinking water from materials ranging from Garde hydraulic fluid to urine in a matter of seconds. Every Garde pilot's flight suit is equipped with one and also inserts a catheter into the pilot, giving access to a long term supply of drinking water on long missions or if the pilot gets stranded.

For resource extraction, there are multiple pieces of equipment that can be used by Gardes to quickly extract water or minerals from a variety of locations, ranging from planets to ice comets.

Genetics and Biology

Sidonian genetic and biological technology is extremely advanced. Along with the genetic manipulation they did to the entire Sidonian population to give them the ability to photosynthesize, they have advanced technology related to cloning, memory extraction, and transfer, artificial wombs, and accelerated training. The Honoka sisters, for example, are a set of cloned, fully trained, and combat-capable Garde pilots but are only 5 years old. Given how often they take casualties while fighting the Gauna, this technology is extremely critical to keep their population numbers from dwindling too much. They also have the ability to near-infinitely prolong the life of any human barring death due to critical injury, however ,the Immortal Ship Committee zealously guards this information for themselves.

Military Tech

Very unsurprisingly, because of the constant threat of attacks by Gauna, Sidonian military technology is not only one of its most advanced fields, but also sees the most research and development. The Garde units, large humanoid-shaped combat mechs, are highly mobile and adaptable multipurpose combat vehicles and advanced virtual-reality training simulators are used to train their pilots. Multiple technologies built around the use of the powerful Heigus Particles have given Sidonians strong power generation, beam weapon and propulsion equipment.

Pics Gallery

Notes & Trivia

The time between Sidonia leaving in 2384, and the present time of the story, 3391, is exactly half of 2014, the year the anime series debuted. 1007.

Articles & References


Knights of Sidonia Sciences & Technologies

Kabizashi | Heigus Particles | The Kabi Deep Space Artifact

Seed Ships

Sidonia | Aposimz

Support Ships & Crafts

Mizuki | Hayakaze | Tsukikazu


Anti-Gauna Missiles | Super High Speed Ballistic Acceleration Device | Interplanetary Missile | Heavy Mass Cannon | Gatling Gun | Small Arms


Type 5 | Type 15 | Type 16 | Type 17 - Shiratsuki - Tsugumori | Type 18 | Tsugumori Custom | Type 19 Prototype - Type 19 | High-Cost Unit's Prototype | Tsugumori Custom 2 | Type 20 - Yukimori

Ochiai's Creations

Blood Nematode

Knights of Sidonia
Anime Season 1 | S1 compilation movie | Season 2 | The Star Where Love is Spun (movie) | Season 3
Subjects & Topics Sidonia | Gauna | Gardes | Technology of Sidonia | Characters of Sidonia |
Manga Volume 1 | Volume 2 | Volume 3 | Volume 4 | Volume 5 | Volume 6 | Volume 7 | Volume 8 | Volume 9 | Volume 10 | Volume 11 | Volume 12 | Volume 13