For general access to the Wolfram Knowledgebase, use entities of type Galaxy instead of GalaxyData.


gives the value of the specified property for the galaxy entity.


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


gives the specified annotation associated with the given property.


  • GalaxyData[] gives a list of all galaxy entities.
  • GalaxyData["Properties"] gives a list of available properties.
  • The specified entity in GalaxyData 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:
  • "AlphanumericName"alphanumeric name
    "AlternateNames"alternate names
    "AltitudeTransit"next transit altitude
    "AngularDiameterFromEarth"angular diameter from Earth
    "AngularRadiusFromEarth"angular radius from Earth
    "ApparentAltitude"apparent altitude
    "ApparentMagnitude"apparent magnitude
    "AzimuthRise"azimuth at rise
    "AzimuthSet"azimuth at set
    "BlueBandMagnitude"blue band magnitude
    "BooleanRise"above the horizon
    "DailyTimeAboveHorizon"daily time above horizon
    "Diameter"average diameter
    "DistanceFromEarth"distance from Earth
    "DistanceFromMilkyWay"distance from the center of the Milky Way galaxy
    "DistanceFromSun"distance from Sun
    "GalacticLatitude"galactic latitude
    "GalacticLongitude"galactic longitude
    "GalaxyType"galaxy type
    "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
    "HubbleType"Hubble type
    "ICNumber"IC number
    "LocalHourAngle"local hour angle
    "MaximalAltitudeTime"next maximum altitude time
    "NGCNumber"NGC number
    "PGCNumber"PGC number
    "RadialVelocity"radial velocity
    "Radius"average radius
    "RightAscension"right ascension
    "RiseTime"next rise
    "SetTime"next set
    "SiderealHourAngle"sidereal hour angle
    "SurfaceBrightness"surface brightness
    "TransitTime"next transit time
    "VisualBandMagnitude"visual band magnitude
  • Some properties are available for GalaxyData as a whole and can be given using the form GalaxyData[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 GalaxyData[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
    Totalreturns the total
    Lengththe number of elements


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Basic Examples  (4)

Use for discovery:

Determine the distance to a galaxy:

Find the equatorial coordinates of a galaxy:

Find the current sky position of a galaxy from your location:

Scope  (2)

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:

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


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


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


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


@misc{reference.wolfram_2024_galaxydata, author="Wolfram Research", title="{GalaxyData}", year="2014", howpublished="\url{}", note=[Accessed: 16-July-2024 ]}


@online{reference.wolfram_2024_galaxydata, organization={Wolfram Research}, title={GalaxyData}, year={2014}, url={}, note=[Accessed: 16-July-2024 ]}