Callisto is one of Jupiter's moons, it's second-largest moon (after Ganymede) and the third-largest in the Sol system. Its orbit requires it to be tidally locked – one side constantly faces Jupiter. Its namesake is from Greek mythology: a nymph in retinue to the goddess Artemis and one of Zeus's (Roman: Jupiter) consorts.

The moon has a moderate subterranean population as the moon does not enjoy the protection from Jupiter's radiation belts in contrast to Ganymede. The colony has a mining industry but also boasts shipyards, including MCRN Callisto shipyards and the Earth owned UN Callisto shipyards[1] Additionally, a respected university with affiliations to Mars's technical institutes is located in the colony. The hemisphere facing Jupiter includes an observatory focused on Jovian research[2].

Events Edit

At some point prior to the Eros Incident, Callisto was the site of a proxy war between Earth and Mars. As tensions rose over union negotiations, Earth sent in increasing numbers of private security forces while Mars sent in advisors. The groups inflamed the tensions, resulting in Belter groups they backed fighting each other in the stead of Earth and Mars[3].

A little more than a year before the Free Navy Conflict [4], the Free Navy attacks the MCRN shipyard in a covert operation. The operation manages to secure stealth tech – 4, thousand-litre canisters of MCRN energy absorbing coating. The heist is covered up by the destruction of the shipyard by kinetic impacts of pre-accelerated meteors[5].

The impacts were sizable to result in civilian casualties and destruction of colony infrastructure. This includes the cracking and depressurization of at least one of the colony's hard shelters[6].

Callisto was also a location prominent in the Free Navy Conflict. Like many of the outer planets, it embraced control of the Free Navy, as seen in the adoption of Free Navy script as a valid currency[2].

In the latter portions of the war, it was the de facto command center of the Free Navy following the Pella coming into port for repairs. Due to this, the Jovian System saw two large battles, one of which was fought in the vicinity of Callisto's orbit (see the Battle of Callisto). The Free Navy lost several ships but ultimate secured a victory over Micah al-Dujaili's wing of the Consolidated Fleet[7]. Callisto remained the de facto command center of the Free Navy until the departure of Marco Inaros and the Pella to reinforce the Free Navy in the Battle of Medina Station[6].

Notes Edit

TV show references Edit

Season 1 ⸻ Episode"Back to the Butcher" ? ·Joe Miller

·Neville Bosch

Callisto cesium mine collapse
Julie Mao
Season 1 ⸻ Episode"Windmills" ? ·Chrisjen Avasarala

·Elise Holden

Callisto Insurrection
Season 3 ⸻ Episode"Triple Point" ? ·Capt. Kirino
·Lt. Durant
MCRN Shipyard
?? ·Admiral Nguyen

·Lt. Shaffer
·Lt. Mancuso
·Lt. Boyer

Trivia Edit

  • The moon is suspected to house a subterranean ocean, and a possible location for life outside of Earth, not unlike Europa. This topic has not been discussed by the novels but, due to the protomolecule being the first evidence of extra-terrestrial life, either humans have not yet reached the ocean, the ocean does not contain living organisms, or the ocean has not been imagined to exist in the novels.

Etymology and MythologyEdit

As with many ancient myths, multiple versions have survived to the present. The general details on Callisto from mythology are:

  • (For more information on this topic, refer to wikipedia:Callisto_(mythology)). This subsection may be removed per consensus and community standards. (See Thread:9221)
  • She was either a nymph (spirit of land, water, sky, forest, etc.) or the daughter of King Lycaon of Arcadia.
  • She took a vow of chastity so that she could join Artemis as a companion and servant, hunting alongside the goddess in the woods.
  • Disguised as Artemis, Zeus approached her in the woods, seduced her, and tricked her into breaking her vow of chastity. Because of this, she bore a child, Arcas, the namesake of Arcadia.
  • She was transformed into a bear by either Zeus (to hide his infidelity, or Hera (in retribution for Zeus's infidelity), or by Artemis (as punishment for breaking her vow).
  • She was then either killed by Hera, by Artemis at the behest of Hera or to please Hera, or by her son not recognizing his mother in bear form.
  • Out of pity, Zeus elevated her into the sky, naming her Ursa Major with her son becoming Ursa Minor.
  • In later Roman versions, Hera seeks a final punishment and woes to her nurse, Tethys, the wife of Oceanus, and beseeched her to punish Callisto and Arcas. Tethys decided to deprive the pair of water, and so the great bear and the little bear are cursed to circle in the skies, never to dip below the horizon for a refreshing bath or a cool drink.


  1. The Expanse Novel: Nemesis Games, Prologue - Filip
  2. 2.0 2.1 The Expanse Novel: Babylon's Ashes, Chapter 36.
  3. The Expanse Novel: Babylon's Ashes, Chapter 21.
  4. The Expanse Novel: Babylon's Ashes, Chapter 1.
  5. The Expanse Novel: Nemesis Games, Prologue.
  6. 6.0 6.1 The Expanse Novel: Babylon's Ashes, Chapter 47.
  7. The Expanse Novel: Babylon's Ashes, Chapter 42.

External links Edit

  5. Icon-wikipedia-22x22Wikipedia article on Callisto mythology