Hegemone

A confirmed moon in the Jupiter system.

Named · Jupiter XXXIX · S/2003 J 8

Snapshot 2026-09-09 · catalog 1.0.0

Explore Hegemone in Orrery

Physical measurements

Mean radius
— No value in the admitted source set.
GM · gravitational parameter
— No value in the admitted source set.
Mass
— Mass requires an admitted GM estimate.
Mean density
— No value in the admitted source set.

Orbit descriptions

Mean elements describe an average orbit. They are not positions for a chosen date.

JUP347 · ecliptic plane · 2000-01-01.5 TDB
Semimajor axis
23,342,600 km
Sidereal period
728.774 days
Eccentricity
0.357
Inclination to reference plane
152.5°
Argument of periapsis
192.2°
Mean anomaly
241.1°
Ascending node
311.5°
Apsidal / nodal precession periods
53.9 / 78 years
Reference-plane pole RA / Dec
— / —°
Plane tilt to parent equator
—°
Reference center
Not specified in this summary sourceThe summary table identifies a parent system but does not explicitly specify the reference center for each solution. Do not infer a physical-primary center, especially for Pluto’s circumbinary moons.

Orientation

No supported orientation model in the admitted PCK source.

Identity & availability

Stable catalog ID
hegemone
JPL / NAIF satellite ID
539
Names & designations
Hegemone · S/2003 J 8
Discovery / rediscovery years
2003S.S. Sheppard

No validated dated trajectory admitted in catalog 1.0.0. Mean elements are not ephemerides.

No image or global texture admitted in this catalog release.No environment measurements admitted in this catalog release.

Sources & evidence

  1. JPL discovery circumstancestable tr[43] (zero-based); jupiter / Hegemone · References: IAUC 8088
  2. MPC planetary satellite listitems[82]; Jupiter 39
  3. MPC satellite namesitems[66]; Jupiter 39
  4. JPL mean orbital elements#sat_elem row ID=41; Jupiter / Hegemone / NAIF 539 · References: 47

Full catalog, uncertainty and source manifests · All Jupiter moons · Moon model limits