StarClusterRelated Interpreter »
gives the value of a specified property.
gives the value of a list of properties.
gives the value of a specified property modified by qualifier rules quali->vali.
gives the value of a property associated with a particular date specification.
Sample Entity Classes
AlphanumericName alphanumeric name AlternateNames alternate names Altitude altitude AltitudeTransit next transit altitude AngularDiameterFromEarth angular diameter AngularRadiusFromEarth angular radius ApparentAltitude apparent altitude ApparentMagnitude apparent magnitude Azimuth azimuth AzimuthRise azimuth at rise AzimuthSet azimuth at set BlueBandMagnitude blue band magnitude BooleanRise above the horizon Classes classes Constellation constellation DailyTimeAboveHorizon daily time above horizon Declination declination Diameter average diameter DistanceFromEarth distance from Earth DistanceFromSun distance from Sun EntityClasses entity classes GalacticLatitude galactic latitude GalacticLongitude galactic longitude GlobularClusterType Shapley–Sawyer concentration class GreenwichHourAngle Greenwich hour angle HelioCoordinates heliocentric XYZ coordinates ICNumber IC number Image image LocalHourAngle local hour angle MajorAxis major axis MaximalAltitudeTime next maximum altitude time MinorAxis minor axis Name name NGCNumber NGC number ObjectType object type RadialVelocity radial velocity Radius average radius Redshift redshift RightAscension right ascension RiseTime next rise SetTime next set SiderealHourAngle sidereal hour angle TransitTime next transit time VisualBandMagnitude visual band magnitude
- "StarCluster" entities include the majority of star clusters from the Revised New General Catalogue and Index Catalogue, including members of the Messier Catalog.
- "StarCluster" entity classes include groups based on star cluster type, such as "open star clusters" and "globular clusters", as well as groups related to catalog membership, such as "Messier objects".
- Some properties are available for the "StarCluster" entity type as a whole and can be given using the form EntityValue["StarCluster",property]. Such properties include:
"Properties" the list of available properties "PropertyCanonicalNames" the standard names of available properties "SampleEntities" a sample list of available entities (typically of length 10) "SampleEntityClasses" a sample list of available entity classes (typically of length 10) "EntityCount" number of entities available "Entities" the list of available entities "EntityCanonicalNames" the standard names of available entities "EntityClasses" the list of available entity classes "EntityClassCanonicalNames" the standard names of available entity classes "PropertyClasses" the list of available property classes "PropertyClassCanonicalNames" the standard names of available property classes "PropertyCount" number of properties available
- The following annotations can be used in the third argument of EntityValue["StarCluster",property,annotation]:
"Source" source information for the property "Date" the date associated with the entity-property value (if any) "EntityAssociation" an association of entities and entity-property values "PropertyAssociation" an association of properties and entity-property values "EntityPropertyAssociation" an association in which the specified entities are keys, and values are a nested association of properties and entity-property values "PropertyEntityAssociation" an association in which the specified properties are keys, and values are a nested association of entities and entity-property values "Dataset" a dataset in which the specified entities are keys, and values are an association of property names and entity-property values
- The following annotations can be used in the second argument of EntityValue[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 "PhysicalQuantity" the physical quantity associated with the entity-property value "Unit" the unit associated with the entity-property value
- A qualifier value of Automatic indicates that an applicable format of values can be used; e.g. for the "Date" qualifier, this includes a proper date or date span.
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Basic Examples (6)
Implicit Entity Classes (1)
Globular clusters are distributed spherically around the center of the galaxy. Before radio and infrared astronomy, which allow you to see through all the dust that obscures your view of the center of the galaxy, globular clusters could be used to estimate the location of the galactic center.
Globular star clusters are distributed spherically around the center of the galaxy, but open star clusters are mainly confined to the galactic plane. You can use the location of open star clusters to find the galactic plane.