JplSpkEphemerisProvider Class

The common base for classes for loading and accessing JPL SPK files.

Inheritance Hierarchy

SystemObject
  AGI.Foundation.InfrastructureDefinitionalObject
    AGI.Foundation.SpiceJplSpkEphemerisProvider
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Namespace: AGI.Foundation.Spice
Assembly: AGI.Foundation.Models (in AGI.Foundation.Models.dll) Version: 24.1.418.0 (24.1.418.0)

Syntax

C++

Copy

public abstract class JplSpkEphemerisProvider : DefinitionalObject

Public MustInherit Class JplSpkEphemerisProvider
	Inherits DefinitionalObject

public ref class JplSpkEphemerisProvider abstract : public DefinitionalObject

[<AbstractClassAttribute>]
type JplSpkEphemerisProvider =  
    class
        inherit DefinitionalObject
    end

The JplSpkEphemerisProvider type exposes the following members.

Constructors

	Name	Description
	JplSpkEphemerisProvider(JplSpkFile)	Initializes an instance using the specified JplSpkFile instance.
	JplSpkEphemerisProvider(StreamFactory)	Initializes a new instance with the specified stream factory.
	JplSpkEphemerisProvider(String)	Initializes an instance using the specified JPL SPK filename.
	JplSpkEphemerisProvider(JplSpkEphemerisProvider, CopyContext)	Initializes a new instance as a copy of an existing instance.

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Properties

	Name	Description
	File	Gets the JPL SPK file represented by this instance.
	IsFrozen	Gets a value indicating whether this object is frozen. A frozen object cannot be modified and an ObjectFrozenException will be thrown if an attempt is made to do so. (Inherited from DefinitionalObject.)

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Methods

	Name	Description
	CheckForSameDefinition(DefinitionalObject)	Checks to determine if another instance has the same definition as this instance and returns if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IsSameDefinition(Object). (Overrides DefinitionalObjectCheckForSameDefinition(DefinitionalObject).)
	CheckForSameDefinition(JplSpkEphemerisProvider)	Checks to determine if another instance has the same definition as this instance and returns if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IsSameDefinition(Object).
	Clone	Clones this object using the specified context. (Inherited from DefinitionalObject.)
	ComputeCurrentDefinitionHashCode	Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the CheckForSameDefinition(DefinitionalObject) method. (Overrides DefinitionalObjectComputeCurrentDefinitionHashCode.)
	EnumerateDependencies	Enumerates the dependencies of this object by calling EnumerateT(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class. (Overrides DefinitionalObjectEnumerateDependencies(DependencyEnumerator).)
	Equals	Determines whether the specified object is equal to the current object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
	Freeze	Freezes this object. Further attempts to modify it will result in an ObjectFrozenException. (Inherited from DefinitionalObject.)
	FreezeAggregatedObjects	Called by Freeze to also freeze any objects that are considered to be a part of this object. Derived classes which contain additional aggregated objects MUST override this method, call the base implementation, and freeze aggregated objects introduced by the derived class. The objects that need to be frozen in this method are frequently created in this object's constructor and are not settable via properties. (Overrides DefinitionalObjectFreezeAggregatedObjects.)
	GetDefinitionHashCode	Gets a hash code representing the definition of this object. (Inherited from DefinitionalObject.)
	GetHashCode	Serves as the default hash function. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	IsSameDefinition	Determines if this object has the same definition as another object. (Inherited from DefinitionalObject.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ModelSolarSystemUsingPlanetaryDataSupplement	Consistently applies UseForCentralBodyPositions(CentralBodiesFacet) on all of the *.bsp ephemerides available in the STK Planetary Data Supplement to model the entire solar system. The planetary system barycenters are computed first and then their updated positions are applied to the positions of Pluto, the planets, and the planetary moons. Both the central bodies facet and the ephemeris providers will have their planetary system barycenters updated. See the documentation on the individual ephemeris providers to get instructions about how to find the files.
	ModelSolarSystemUsingPublicJplData	Consistently applies UseForCentralBodyPositions(CentralBodiesFacet) on JplDE and some of the *.bsp ephemerides available on the JPL website to model the entire solar system. The Sun and the planetary system barycenters are computed first and then their updated positions are applied to the positions of Ceres, Vesta, Pluto, the planets, and the planetary moons. See the documentation on the individual ephemeris providers to get instructions about how to find or generate the files.
	ThrowIfFrozen	Throws ObjectFrozenException if this object IsFrozen. This method should be called from any method or property that modifies this object. (Inherited from DefinitionalObject.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)
	UseForCentralBodyPositions	Use this ephemeris provider to define the locations of whichever central bodies and barycenters are directly provided by this file.

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Remarks

If STK is installed with the Planetary Data Supplement, several relatively small (less than 200 MB each) *.bsp files are available in the STKData/Spice folder of the STK installation. These files are described in the Readme.txt file in the ReadMe folder inside the STKData/Spice folder. They provide enough data to enable all of the available CentralBodies and PlanetarySystemBarycenters to have their CenterOfMassPoints be defined in terms of the SolarSystemBarycenter within the CentralBodiesFacet with far greater accuracy and precision than the default analytic ephemeris can provide.

If STK or the Planetary Data Supplement are unavailable, the next best option is to go to the website of the Navigation and Ancillary Information Facility (NAIF) of JPL to download *.bsp ephemerides for planets and planetary moons. Some of these can be massive (greater than 1 GB) because they often contain data that extends hundreds of years into the past and future for astronomical purposes. There is typically a small text *.cmt file with the same name as the *.bsp ephemeris that contains information about what data is contained within each *.bsp file.

For asteroids and comets, the best strategy is to go to the website of the Solar System Dynamics (SSD) group of JPL to generate custom *.bsp files using the Horizons Web Application.

Reference

AGI.Foundation.Spice Namespace

Inheritance Hierarchy