Kerberos

A confirmed moon in the Pluto system.

Named · Pluto IV · S/2011 (134340) 1

Snapshot 2026-09-09 · catalog 1.0.0

Explore Kerberos in Orrery

Physical measurements

Mean radius
6 ± 1 kmmeasured · Source estimate; uncertainty is the source-reported standard error when available.
GM · gravitational parameter
< 0.0002 km³ s⁻²upper-limit · Source bound; confidence level not specified in the summary table.
Mass
< 2.9966e+15 kgupper-limit · GM bound converted using nominal CODATA G; confidence unspecified, not a measured mass.
Mean density
— Source reports no value.

Orbit descriptions

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

PLU060 · equatorial plane · 2000-01-01.5 TDB
Semimajor axis
58,300 km
Sidereal period
32.17 days
Eccentricity
0.01
Inclination to reference plane
0.4°
Argument of periapsis
32.1°
Mean anomaly
276.1°
Ascending node
314.3°
Apsidal / nodal precession periods
— / 9 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
kerberos
JPL / NAIF satellite ID
904
Names & designations
Kerberos · S/2011 (134340) 1
Discovery / rediscovery years
2011M.R. Showalter, D.P. Hamilton, S.A. Stern, H.A. Weaver, A.J. Steffl, L.A. Young

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[465] (zero-based); pluto / Kerberos · References: IAUC 9221
  2. JPL confirmed small-body satellitesdata[326].sat; primary=134340 · References: Showalter et al. (2011), CBET 2769
  3. JPL physical parameters#sat_phys_par; Pluto / Kerberos / NAIF 904; mean radius · References: 3
  4. JPL physical parameters#sat_phys_par; Pluto / Kerberos / NAIF 904; GM · References: PLU060
  5. NIST CODATA 2022Table of universal constants, Newtonian constant of gravitationVerified numeric transcription; see acquisition notes in the download.
  6. JPL physical parameters#sat_phys_par; Pluto / Kerberos / NAIF 904; density · References: n/a
  7. JPL mean orbital elements#sat_elem row ID=458; Pluto / Kerberos / NAIF 904 · References: 6

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