For general access to the Wolfram Knowledgebase, use entities of type PlanetaryMoon instead of PlanetaryMoonData.


gives the value of the specified property for the moon entity of a planet or minor planet.


gives a list of property values for the specified moon entities.


gives the specified annotation associated with the property.


  • PlanetaryMoonData[] gives a list of all planetary moon entities.
  • PlanetaryMoonData["Properties"] gives a list of available properties.
  • The specified entity in PlanetaryMoonData can be an Entity, EntityClass, entity canonical name, or list thereof.
  • The specified property can be an EntityProperty, EntityPropertyClass, property canonical name, or list of properties.
  • Properties that do not apply or are not known in a particular case are indicated by Missing[].
  • Properties include:
  • "AbsoluteMagnitudeH"absolute magnitude H
    "AlphanumericName"alphanumeric name
    "AlternateNames"alternate names
    "AltitudeMaximum"next maximum altitude
    "AltitudeTransit"next transit altitude
    "AngularDiameterFromEarth"angular diameter as seen from Earth
    "AngularRadiusFromEarth"angular radius as seen from Earth
    "Apoapsis"largest distance from orbit center
    "ApoapsisTime"next apoapsis time
    "ApoapsisTimeLast"last apoapsis time
    "ApparentAltitude"apparent altitude
    "ApparentMagnitude"apparent magnitude
    "AscendingNodeLongitude"longitude of ascending node
    "AtmosphericComposition"atmospheric composition
    "AtmosphericPressure"atmospheric pressure
    "AverageDistanceFromEarth"average distance from Earth
    "AverageOrbitDistance"average orbit distance
    "AverageOrbitVelocity"average orbit velocity
    "AverageTemperature"average temperature
    "AzimuthRise"azimuth at rise
    "AzimuthSet"azimuth at set
    "BooleanRise"above the horizon
    "CylindricalEquidistantTexture"cylindrical equidistant texture
    "DailyTimeAboveHorizon"daily time above horizon
    "Density"mean density
    "Diameter"average diameter
    "DiscoveryYear"discovery year
    "DistanceFromEarth"distance from Earth
    "DistanceFromSun"distance from Sun
    "EccentricAnomaly"eccentric anomaly
    "Eccentricity"orbital eccentricity
    "EffectiveTemperature"effective temperature
    "EquatorialAngularVelocity"equatorial angular velocity
    "EquatorialCircumference"equatorial circumference
    "EquatorialDiameter"equatorial diameter
    "EquatorialFrequency"equatorial frequency
    "EquatorialRadius"equatorial radius
    "EscapeVelocity"escape velocity
    "FarthestPlanet"farthest solar system planet
    "GalacticLatitude"galactic latitude
    "GalacticLongitude"galactic longitude
    "GeocentricEclipticLatitude"geocentric ecliptic latitude
    "GeocentricEclipticLongitude"geocentric ecliptic longitude
    "GravitationalConstantMassProduct"standard gravitational parameter
    "GreenwichHourAngle"Greenwich hour angle
    "HeliocentricEclipticLatitude"heliocentric ecliptic latitude
    "HeliocentricEclipticLongitude"heliocentric ecliptic longitude
    "HelioCoordinates"heliocentric XYZ coordinates
    "HillRadius"Hill radius
    "Inclination"orbital inclination
    "LocalHourAngle"local hour angle
    "MajorAxis"major axis
    "MaximalAltitudeTime"next maximum altitude time
    "MaximumTemperature"maximum temperature
    "MinimumTemperature"minimum temperature
    "MinorAxis"minor axis
    "MomentOfInertia"rotational moment of inertia
    "NearestPlanet"nearest solar system planet
    "OrbitalAngularMomentum"orbital angular momentum
    "OrbitalKineticEnergy"orbital kinetic energy
    "OrbitalMomentOfInertia"orbital moment of inertia
    "OrbitCenter"orbit center
    "OrbitCircumference"orbit circumference
    "OrbitPeriod"orbital period
    "Periapsis"nearest distance from orbit center
    "PeriapsisArgument"argument of periapsis
    "PeriapsisTime"next periapsis time
    "PeriapsisTimeLast"last periapsis time
    "PolarDiameter"polar diameter
    "PolarRadius"polar radius
    "Radius"average radius
    "RetrogradeApparentMotionQuery"apparent direction
    "RightAscension"right ascension
    "RiseTime"next rise
    "RocheLimit"Roche limit
    "RotationalAngularMomentum"rotational angular momentum
    "RotationPeriod"rotation period
    "SemimajorAxis"orbital semimajor axis
    "SemiminorAxis"orbital semiminor axis
    "SetTime"next set
    "SiderealHourAngle"sidereal hour angle
    "SolarDay"solar day
    "SolidAngleFromEarth"solid angle
    "StationaryOrbitRadius"stationary orbit radius
    "StationaryOrbitSpeed"stationary orbit speed
    "SunElongation"elongation from the Sun
    "SurfaceArea"surface area
    "TexturedSurface"3D graphic
    "TransitTime"next transit time
    "TrueAnomaly"true anomaly
  • Some properties are available for PlanetaryMoonData as a whole and can be given using the form PlanetaryMoonData[property]. Such properties include:
  • "Entities"all available entities
    "EntityCount"total number of available entities
    "Classes"all available entity classes
    "EntityClassCount"total number of available entity classes
    "SampleEntities"list of sample entities
    "SampleEntityClasses"list of sample entity classes
    "EntityCanonicalNames"list of all entity canonical names
    "PropertyCanonicalNames"list of all property canonical names
    "EntityClassCanonicalNames"list of all entity class canonical names
    "RandomEntities"pseudorandom sample entities
    {"RandomEntities",n}n pseudorandom entities
    "RandomEntityClasses"pseudorandom sample entity classes
    {"RandomEntityClasses",n}n pseudorandom entity classes
  • The following annotations can be used in the third argument of PlanetaryMoonData[entity,property,annotation]:
  • "Qualifiers"the list of possible qualifiers for the property
    "QualifierValues"the list of possible values that can be given to each qualifier
    "DefaultQualifierValues"the list of default values for the property's qualifiers
    "Description"a brief textual description of the property
    "Definition"a detailed textual definition of the property
    "Source"source information for the property
    "Date"the date associated with the entity-property value (if any)
    "PhysicalQuantity"the physical quantity associated with the entity-property value
    "Unit"the unit associated with the entity-property value
    "EntityAssociation"an association of entities and entity-property values
    "PropertyAssociation"an association of properties and entity-property values
  • If a function is provided as an annotation, it will be used to aggregate the result data. Typical aggregation functions include:
  • Minthe minimum value
    Maxthe maximum value
    Meanthe mean value
    Commonestthe most frequently occurring value
    Medianthe median value
    Totalreturn the total
    Lengththe number of elements


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Basic Examples  (6)

Use for discovery:

Find the mass of a moon:

Compare the orbit distance of a moon to the radius of the planet it orbits:

Get a list of classes of moons:

Look up the orbit periods of the moons of Neptune:

Get a list of all available moons:

Scope  (4)

The known satellites of Neptune:

Diameter of each satellite:

Orbital semimajor axis:

The minor planet Eris has one known satellite:

Orbital semimajor axis:

Date qualifiers can accept an explicit DateObject or queries that evaluate to a DateObject:

Date qualifiers can also be specified using Dated:

Location qualifiers can accept an explicit GeoPosition, location-based Entity objects, or queries that evaluate to one of these:

Applications  (3)

The corresponding plot for all known planetary moons, with a line for each planet:

Find the total number of known planetary moons in the solar system:

Make a log-rank plot of the masses of the moons, with names as tooltips:

Properties & Relations  (1)

PlanetaryMoonData can be combined with SolarSystemFeatureData to create maps with labeled features:

Neat Examples  (1)

Plot diameter against discovery year for the known moons of Saturn:

Wolfram Research (2014), PlanetaryMoonData, Wolfram Language function,


Wolfram Research (2014), PlanetaryMoonData, Wolfram Language function,


Wolfram Language. 2014. "PlanetaryMoonData." Wolfram Language & System Documentation Center. Wolfram Research.


Wolfram Language. (2014). PlanetaryMoonData. Wolfram Language & System Documentation Center. Retrieved from


@misc{reference.wolfram_2024_planetarymoondata, author="Wolfram Research", title="{PlanetaryMoonData}", year="2014", howpublished="\url{}", note=[Accessed: 22-June-2024 ]}


@online{reference.wolfram_2024_planetarymoondata, organization={Wolfram Research}, title={PlanetaryMoonData}, year={2014}, url={}, note=[Accessed: 22-June-2024 ]}