--- title: "Satellite" language: "en" type: "Entity" summary: "Artificial satellites that orbit Earth." canonical_url: "https://reference.wolfram.com/language/ref/entity/Satellite.html" source: "Wolfram Language Documentation" related_guides: - title: "Entity Types" link: "https://reference.wolfram.com/language/guide/EntityTypes.en.md" --- # Satellite Artificial satellites that orbit Earth. [Related Interpreter](https://reference.wolfram.com/language/ref/interpreter/Satellite.en.md) Entity["Satellite", name] or Entity[...] represents an entity of type "Satellite". Entity[...][prop] gives the value of a specified property. Entity[...][{propi, …}] gives the value of a list of properties. Entity[...][prop, {quali -> vali, …}] gives the value of a specified property modified by qualifier rules quali -> vali. Entity[...][Dated[prop, date]] gives the value of a property associated with a particular date specification. EntityClass["Satellite", {propi -> speci, …}] represents a class of entities with values of propi defined by speci. ## Sample Entities * Entity["Satellite", "25280"]Entity["Satellite", "25544"]Entity["Satellite", "03626"]Entity["Satellite", "25867"]Entity["Satellite", "17297"]Entity["Satellite", "23754"]Entity["Satellite", "14780"]Entity["Satellite", "28927"]Entity["Satellite", "43435"]Entity["Satellite", "15237"]**…** ## Sample Entity Classes * EntityClass["Satellite", "SiriusFM"]EntityClass["Satellite", "GammaRayObservatories"]EntityClass["Satellite", "INSATSatellites"]EntityClass["Satellite", "GLONASS"]EntityClass["Satellite", "SpaceXDragon"]EntityClass["Satellite", "SpaceTelescopes"]EntityClass["Satellite", "Thor"]EntityClass["Satellite", "SpaceShuttleChallenger"]EntityClass["Satellite", "UltravioletObservatories"]EntityClass["Satellite", "Skynet"]**…** ## Properties | | | | --------------------------- | ----------------------------- | | AlternateNames | alternate names | | Altitude | altitude | | ApogeeDistance | apogee distance | | AscendingNodeLongitude | longitude of ascending node Ω | | AverageElevationWGS84 | average altitude | | AverageVelocity | average orbit velocity | | Azimuth | azimuth | | BooleanRise | above the horizon | | Constellation | constellation | | Contractor | contractor | | CountryOfContractor | contractor country | | CountryOfOperatorOwner | operator countries | | DecayedDate | decay date | | Declination | declination | | Disciplines | disciplines | | DistanceFromLocation | distance | | DryMass | dry mass | | Eccentricity | orbital eccentricity | | ElevationWGS84 | orbital altitude | | EntityClasses | entity classes | | EntityTypeList | entity type list | | ExpectedLifetime | expected lifetime | | FundingAgencies | funding agencies | | GetTLETime | TLE epoch | | Heading | heading | | Image | image | | InclinationOsculating | inclination | | LandingDate | landing date | | LaunchDate | launch date | | LaunchMass | launch mass | | LaunchSite | launch site | | LaunchVehicle | launch vehicle | | MagneticAzimuth | magnetic azimuth | | MeanAnomaly | mean anomaly | | MeanMotion | mean motion | | Name | name | | NORADNumber | NORAD number | | NSSDCID | international designator | | ObjectType | object type | | OperatorOwner | operator | | Orbiter | orbiter | | OrbitType | orbit type | | PerigeeArgument | argument of periapsis ω | | PerigeeDistance | perigee distance | | PerigeeLongitude | longitude of periapsis ϖ | | PeriodOsculating | orbital period | | Position | position | | PositionLine | position line | | Power | power in watts | | PrimaryCrew | primary crew | | Purpose | purpose | | RightAscension | right ascension | | RiseTime | next rise | | SatelliteVisibilityDistance | satellite visibility distance | | SemimajorAxis | semimajor axis | | SemiminorAxis | semiminor axis | | SetTime | next set | | SunAngle | sun angle | | TimeInOrbit | time in orbit | | TransmissionDelay | transmission delay | | Users | user type | | Velocity | instantaneous velocity | | VisibleRegionRadius | visible region radius | ## Details * ``"Satellite"`` entities include the collection of objects that orbit Earth and are tracked by USSTRATCOM and NORAD. Classified satellites are not included. * ``"Satellite"`` entity classes include groups based primarily on mission type, such as GPS satellites, or satellite constellation, such as EchoStar satellites. * Some properties are available for the ``"Satellite"`` entity type as a whole and can be given using the form ``EntityValue["Satellite", 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["Satellite", 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. --- ## Examples (8) ### Basic Examples (3) Use ctrl+= for entity discovery: ```wl In[1]:= \[FreeformPrompt]["Hubble Telescope"] Out[1]= Entity["Satellite", "20580"] ``` --- Find a property value for an entity: ```wl In[1]:= Entity["Satellite", "24792"]["LaunchDate"] Out[1]= DateObject[{1997, 5, 5, 9, 55, 0.}, "Instant", "Gregorian", -5.] ``` --- Retrieve a dataset of all available properties for an entity: ```wl In[1]:= Entity["Satellite", "25544"]["Dataset"] Out[1]= Dataset[Association[EntityProperty["Satellite", "AlternateNames"] -> Missing["NotAvailable"], EntityProperty["Satellite", "Altitude"] -> Quantity[MixedMagnitude[{-73, -4, -47.61806210538339}], MixedUnit[{"AngularDegrees", "Arcminutes", ... ellites"], EntityClass["Satellite", "BrightSatellite"], EntityClass["Satellite", "MannedMission"]}, EntityProperty["Thing", "EntityTypeList"] -> {EntityType["Satellite"]}, EntityProperty["Thing", "Name"] -> "International Space Station"]] ``` --- ### Scope (4) #### Qualifiers (4) Some properties allow you to specify dates: ```wl In[1]:= EntityValue[EntityProperty["Satellite", "Position"], "Qualifiers"] Out[1]= {"Date", "GeoVariant"} In[2]:= EntityValue[\[FreeformPrompt]["international space station"], EntityProperty["Satellite", "Position", {"Date" -> DateObject[{2013, 4, 3, 19, 30, 0}]}]] Out[2]= GeoPosition[{50.1053, 3.23771, 409323., 3.5740206*^9}] ``` --- Some properties allow you to specify dates and locations: ```wl In[1]:= EntityValue[EntityProperty["Satellite", "RiseTime"], "Qualifiers"] Out[1]= {"Date", "Location"} In[2]:= EntityValue[\[FreeformPrompt]["international space station"], EntityProperty["Satellite", "RiseTime", {"Date" -> DateObject[{2019, 10, 3, 20, 0, 0}], "Location" -> \[FreeformPrompt]["San Francisco"]}]] Out[2]= DateObject[{2019, 10, 3, 17, 35}, "Minute", "Gregorian", -7.] ``` --- Date qualifiers can accept an explicit ``DateObject`` or queries that evaluate to a ``DateObject`` : ```wl In[1]:= EntityValue[\[FreeformPrompt]["international space station"], EntityProperty["Satellite", "Altitude", {"Date" -> #}]& /@ {DateObject[{2014, 4, 9, 22, 0, 0}], \[FreeformPrompt]["birth date of Willow Smith"]}] Out[1]= {Quantity[MixedMagnitude[{-29, -53, -7.61426}], MixedUnit[{"AngularDegrees", "Arcminutes", "Arcseconds"}]], Quantity[MixedMagnitude[{-52, -56, -49.6926}], MixedUnit[{"AngularDegrees", "Arcminutes", "Arcseconds"}]]} ``` --- Location qualifiers can accept an explicit ``GeoPosition``, location-based ``Entity`` objects, or queries that evaluate to one of these: ```wl In[1]:= EntityValue[\[FreeformPrompt]["international space station"], EntityProperty["Satellite", "RiseTime", {"Location" -> #}]& /@ {GeoPosition[{40.1, -88.2}], \[FreeformPrompt]["Joplin"], \[FreeformPrompt]["capital city of Iowa"]}] Out[1]= {DateObject[{2025, 6, 26, 6, 55}, "Minute", "Gregorian", -5.], DateObject[{2025, 6, 26, 6, 55}, "Minute", "Gregorian", -5.], DateObject[{2025, 6, 26, 6, 54}, "Minute", "Gregorian", -5.]} ``` ### Neat Examples (1) Compute the current position of the International Space Station: ```wl In[1]:= With[{data = EntityValue[\[FreeformPrompt]["international space station"], {"Position", "PositionLine"}]}, GeoGraphics[{Gray, Thickness[.005], Arrowheads[{{0.05, 0.4}, {0.05, 0.13}}], Arrow@@data[[2]], Red, PointSize[.01], Point[data[[1]]], Opacity[.1], Black, GeoVisibleRegion[data[[1]]]}, GeoCenter -> data[[1]], GeoRange -> "World"]] Out[1]= [image] ``` ## See Also * [`Rocket`](https://reference.wolfram.com/language/ref/entity/Rocket.en.md) * [`DeepSpaceProbe`](https://reference.wolfram.com/language/ref/entity/DeepSpaceProbe.en.md) * [`MannedSpaceMission`](https://reference.wolfram.com/language/ref/entity/MannedSpaceMission.en.md) * [`Satellite`](https://reference.wolfram.com/language/ref/interpreter/Satellite.en.md) * [`ComputedSatellite`](https://reference.wolfram.com/language/ref/interpreter/ComputedSatellite.en.md) * [`Satellite`](https://reference.wolfram.com/language/ref/textcontent/Satellite.en.md) ## Related Guides * [Entity Types](https://reference.wolfram.com/language/guide/EntityTypes.en.md) ## Related Links * [Satellite Source Information](http://www.wolfram.com/knowledgebase/source-information/?page=SatelliteData) ## History * [Introduced in 2019 (12.0)](https://reference.wolfram.com/language/guide/SummaryOfNewFeaturesIn120.en.md)