Pasithee (Jupiter moon)

Physical characteristics

Pasithee is tiny by planetary standards, with an estimated diameter of roughly 2 kilometres. Like many small outer satellites it is irregular in shape rather than spherical; observations therefore describe it as non-spherical. Its surface is presumed dark and composed of rock mixed with ices, a typical composition for distant, captured objects in the outer Jovian system. Very little is known about its rotation period, surface features, or precise composition because Pasithee is faint and challenging to observe except with large telescopes.

Orbit and dynamical group

The moon orbits Jupiter at an average distance near 23.3 million kilometres and completes one revolution in about 726.9 days. Its orbital path is strongly inclined and retrograde: the inclination is about 166 degrees to the ecliptic (roughly 164 degrees relative to Jupiter's equator), and the orbit has a substantial eccentricity of approximately 0.329. These parameters indicate a distant, elongated orbit shaped by past gravitational interactions; the eccentricity is noted in observational summaries of the object (eccentricity data) and the inclination relative to the solar system plane appears in catalogs (inclination notes).

• Mean orbital distance: ~23,307,000 km
• Orbital period: ~726.933 days
• Inclination: ~166° to the ecliptic
• Eccentricity: ~0.3289

Pasithee is classified as a member of the Carme group, a family of similarly retrograde irregular satellites that share comparable distances and inclinations and are believed to have a common origin, possibly a captured asteroid or a fragmented progenitor. See more on the group's characteristics via Carme group references.

Naming and cultural origin

The name Pasithee follows the convention of naming Jovian moons after characters associated with Zeus (the Greek counterpart of Jupiter). Pasithee is a figure from Greek mythology often associated with one of the Charites, and in later tradition identified with Aglaea; she is named in myth as a consort of Hypnos (Sleep) and associated with aspects of charm and hallucinatory trance. The mythological background is summarized in classical name lists and myth references (Charites, Zeus, Hypnos).

Discovery and scientific context

Pasithee was first spotted in 2001 using ground-based telescopes and was tracked over subsequent months to confirm its orbit. The discovery team at the University of Hawaii published the initial designation S/2001 J 6 after follow-up astrometry identified a consistent, bound orbit around Jupiter; the discovery year and designation are often cited in surveys of Jovian satellites (2001 discovery). Ongoing study of objects like Pasithee helps astronomers understand the population of irregular satellites, the processes that capture and disrupt small bodies in giant planet systems, and the collisional history implied by families such as the Carme group.

Because Pasithee is faint and distant, most detailed information remains limited. Continued observations with modern large telescopes and archival reanalysis may refine its size, rotation, color, and precise orbit, contributing to a better picture of Jupiter's irregular satellite system and the Solar System's dynamical past.

Additional resources and catalog entries about Pasithee and related moons are available through discovery-team notes and planetary satellite databases linked here: non-spherical description, team overview, principal investigator notes, discovery year, inclination details, eccentricity reference, naming myth 1, naming myth 2, myth: Hypnos, Carme group overview.