Class FieldKeplerianOrbit<T extends CalculusFieldElement<T>>
- java.lang.Object
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- org.orekit.orbits.FieldOrbit<T>
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- org.orekit.orbits.FieldKeplerianOrbit<T>
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- Type Parameters:
T- type of the field elements
- All Implemented Interfaces:
PositionAngleBased,FieldTimeShiftable<FieldOrbit<T>,T>,FieldTimeStamped<T>,TimeShiftable<FieldOrbit<T>>,FieldPVCoordinatesProvider<T>
public class FieldKeplerianOrbit<T extends CalculusFieldElement<T>> extends FieldOrbit<T> implements PositionAngleBased
This class handles traditional Keplerian orbital parameters.The parameters used internally are the classical Keplerian elements:
a e i ω Ω vwhere ω stands for the Perigee Argument, Ω stands for the Right Ascension of the Ascending Node and v stands for the true anomaly.This class supports hyperbolic orbits, using the convention that semi major axis is negative for such orbits (and of course eccentricity is greater than 1).
When orbit is either equatorial or circular, some Keplerian elements (more precisely ω and Ω) become ambiguous so this class should not be used for such orbits. For this reason,
equinoctial orbitsis the recommended way to represent orbits.The instance
KeplerianOrbitis guaranteed to be immutable.- Since:
- 9.0
- Author:
- Luc Maisonobe, Guylaine Prat, Fabien Maussion, Véronique Pommier-Maurussane, Andrea Antolino
- See Also:
Orbit,CircularOrbit,CartesianOrbit,EquinoctialOrbit
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Constructor Summary
Constructors Constructor Description FieldKeplerianOrbit(Field<T> field, KeplerianOrbit op)Constructor from Field and KeplerianOrbit.FieldKeplerianOrbit(Field<T> field, Orbit op)Constructor from Field and Orbit.FieldKeplerianOrbit(FieldOrbit<T> op)Constructor from any kind of orbital parameters.FieldKeplerianOrbit(FieldPVCoordinates<T> FieldPVCoordinates, Frame frame, FieldAbsoluteDate<T> date, T mu)Constructor from Cartesian parameters.FieldKeplerianOrbit(TimeStampedFieldPVCoordinates<T> pvCoordinates, Frame frame, T mu)Constructor from Cartesian parameters.FieldKeplerianOrbit(T a, T e, T i, T pa, T raan, T anomaly, PositionAngleType type, Frame frame, FieldAbsoluteDate<T> date, T mu)Creates a new instance.FieldKeplerianOrbit(T a, T e, T i, T pa, T raan, T anomaly, T aDot, T eDot, T iDot, T paDot, T raanDot, T anomalyDot, PositionAngleType type, Frame frame, FieldAbsoluteDate<T> date, T mu)Creates a new instance.
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description voidaddKeplerContribution(PositionAngleType type, T gm, T[] pDot)Add the contribution of the Keplerian motion to parameters derivativesprotected T[][]computeJacobianEccentricWrtCartesian()Compute the Jacobian of the orbital parameters with eccentric angle with respect to the Cartesian parameters.protected T[][]computeJacobianMeanWrtCartesian()Compute the Jacobian of the orbital parameters with mean angle with respect to the Cartesian parameters.protected T[][]computeJacobianTrueWrtCartesian()Compute the Jacobian of the orbital parameters with true angle with respect to the Cartesian parameters.TgetA()Get the semi-major axis.TgetADot()Get the semi-major axis derivative.TgetAnomaly(PositionAngleType type)Get the anomaly.TgetAnomalyDot(PositionAngleType type)Get the anomaly derivative.PositionAngleTypegetCachedPositionAngleType()Get the cachedPositionAngleType.TgetE()Get the eccentricity.TgetEccentricAnomaly()Get the eccentric anomaly.TgetEccentricAnomalyDot()Get the eccentric anomaly derivative.TgetEDot()Get the eccentricity derivative.TgetEquinoctialEx()Get the first component of the equinoctial eccentricity vector.TgetEquinoctialExDot()Get the first component of the equinoctial eccentricity vector.TgetEquinoctialEy()Get the second component of the equinoctial eccentricity vector.TgetEquinoctialEyDot()Get the second component of the equinoctial eccentricity vector.TgetHx()Get the first component of the inclination vector.TgetHxDot()Get the first component of the inclination vector derivative.TgetHy()Get the second component of the inclination vector.TgetHyDot()Get the second component of the inclination vector derivative.TgetI()Get the inclination.TgetIDot()Get the inclination derivative.TgetLE()Get the eccentric longitude argument.TgetLEDot()Get the eccentric longitude argument derivative.TgetLM()Get the mean longitude argument.TgetLMDot()Get the mean longitude argument derivative.TgetLv()Get the true longitude argument.TgetLvDot()Get the true longitude argument derivative.TgetMeanAnomaly()Get the mean anomaly.TgetMeanAnomalyDot()Get the mean anomaly derivative.TgetPerigeeArgument()Get the perigee argument.TgetPerigeeArgumentDot()Get the perigee argument derivative.TgetRightAscensionOfAscendingNode()Get the right ascension of the ascending node.TgetRightAscensionOfAscendingNodeDot()Get the right ascension of the ascending node derivative.TgetTrueAnomaly()Get the true anomaly.TgetTrueAnomalyDot()Get the true anomaly derivative.OrbitTypegetType()Get the orbit type.booleanhasDerivatives()Check if orbit includes derivatives.booleanhasRates()Tells whether the instance holds rates (first-order time derivatives) for dependent variables.protected FieldVector3D<T>initPosition()Compute the position coordinates from the canonical parameters.protected TimeStampedFieldPVCoordinates<T>initPVCoordinates()Compute the position/velocity coordinates from the canonical parameters.FieldKeplerianOrbit<T>removeRates()Create a new instance such thatPositionAngleBased.hasRates()is false.FieldKeplerianOrbit<T>shiftedBy(double dt)Get a time-shifted instance.FieldKeplerianOrbit<T>shiftedBy(T dt)Get a time-shifted orbit.KeplerianOrbittoOrbit()Transforms the FieldOrbit instance into an Orbit instance.StringtoString()Returns a string representation of this Keplerian parameters object.-
Methods inherited from class org.orekit.orbits.FieldOrbit
fillHalfRow, fillHalfRow, fillHalfRow, fillHalfRow, fillHalfRow, fillHalfRow, getDate, getField, getFrame, getJacobianWrtCartesian, getJacobianWrtParameters, getKeplerianMeanMotion, getKeplerianPeriod, getMeanAnomalyDotWrtA, getMu, getOne, getPosition, getPosition, getPVCoordinates, getPVCoordinates, getPVCoordinates, getZero, hasNonKeplerianAcceleration, isElliptical
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Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
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Methods inherited from interface org.orekit.utils.FieldPVCoordinatesProvider
getPosition
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Methods inherited from interface org.orekit.time.FieldTimeStamped
durationFrom
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Constructor Detail
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FieldKeplerianOrbit
public FieldKeplerianOrbit(T a, T e, T i, T pa, T raan, T anomaly, PositionAngleType type, Frame frame, FieldAbsoluteDate<T> date, T mu) throws IllegalArgumentException
Creates a new instance.- Parameters:
a- semi-major axis (m), negative for hyperbolic orbitse- eccentricity (positive or equal to 0)i- inclination (rad)pa- perigee argument (ω, rad)raan- right ascension of ascending node (Ω, rad)anomaly- mean, eccentric or true anomaly (rad)type- type of anomalyframe- the frame in which the parameters are defined (must be apseudo-inertial frame)date- date of the orbital parametersmu- central attraction coefficient (m³/s²)- Throws:
IllegalArgumentException- if frame is not apseudo-inertial frameor a and e don't match for hyperbolic orbits, or v is out of range for hyperbolic orbits
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FieldKeplerianOrbit
public FieldKeplerianOrbit(T a, T e, T i, T pa, T raan, T anomaly, T aDot, T eDot, T iDot, T paDot, T raanDot, T anomalyDot, PositionAngleType type, Frame frame, FieldAbsoluteDate<T> date, T mu) throws IllegalArgumentException
Creates a new instance.- Parameters:
a- semi-major axis (m), negative for hyperbolic orbitse- eccentricity (positive or equal to 0)i- inclination (rad)pa- perigee argument (ω, rad)raan- right ascension of ascending node (Ω, rad)anomaly- mean, eccentric or true anomaly (rad)aDot- semi-major axis derivative, null if unknown (m/s)eDot- eccentricity derivative, null if unknowniDot- inclination derivative, null if unknown (rad/s)paDot- perigee argument derivative, null if unknown (rad/s)raanDot- right ascension of ascending node derivative, null if unknown (rad/s)anomalyDot- mean, eccentric or true anomaly derivative, null if unknown (rad/s)type- type of anomalyframe- the frame in which the parameters are defined (must be apseudo-inertial frame)date- date of the orbital parametersmu- central attraction coefficient (m³/s²)- Throws:
IllegalArgumentException- if frame is not apseudo-inertial frameor a and e don't match for hyperbolic orbits, or v is out of range for hyperbolic orbits
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FieldKeplerianOrbit
public FieldKeplerianOrbit(TimeStampedFieldPVCoordinates<T> pvCoordinates, Frame frame, T mu) throws IllegalArgumentException
Constructor from Cartesian parameters.The acceleration provided in
FieldPVCoordinatesis accessible usingFieldOrbit.getPVCoordinates()andFieldOrbit.getPVCoordinates(Frame). All other methods usemuand the position to compute the acceleration, includingshiftedBy(CalculusFieldElement)andFieldOrbit.getPVCoordinates(FieldAbsoluteDate, Frame).- Parameters:
pvCoordinates- the PVCoordinates of the satelliteframe- the frame in which are defined theFieldPVCoordinates(must be apseudo-inertial frame)mu- central attraction coefficient (m³/s²)- Throws:
IllegalArgumentException- if frame is not apseudo-inertial frame
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FieldKeplerianOrbit
public FieldKeplerianOrbit(FieldPVCoordinates<T> FieldPVCoordinates, Frame frame, FieldAbsoluteDate<T> date, T mu) throws IllegalArgumentException
Constructor from Cartesian parameters.The acceleration provided in
FieldPVCoordinatesis accessible usingFieldOrbit.getPVCoordinates()andFieldOrbit.getPVCoordinates(Frame). All other methods usemuand the position to compute the acceleration, includingshiftedBy(CalculusFieldElement)andFieldOrbit.getPVCoordinates(FieldAbsoluteDate, Frame).- Parameters:
FieldPVCoordinates- the PVCoordinates of the satelliteframe- the frame in which are defined theFieldPVCoordinates(must be apseudo-inertial frame)date- date of the orbital parametersmu- central attraction coefficient (m³/s²)- Throws:
IllegalArgumentException- if frame is not apseudo-inertial frame
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FieldKeplerianOrbit
public FieldKeplerianOrbit(FieldOrbit<T> op)
Constructor from any kind of orbital parameters.- Parameters:
op- orbital parameters to copy
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FieldKeplerianOrbit
public FieldKeplerianOrbit(Field<T> field, KeplerianOrbit op)
Constructor from Field and KeplerianOrbit.Build a FieldKeplerianOrbit from non-Field KeplerianOrbit.
- Parameters:
field- CalculusField to base object onop- non-field orbit with only "constant" terms- Since:
- 12.0
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Method Detail
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getType
public OrbitType getType()
Get the orbit type.- Specified by:
getTypein classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- orbit type
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getA
public T getA()
Get the semi-major axis.Note that the semi-major axis is considered negative for hyperbolic orbits.
- Specified by:
getAin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- semi-major axis (m)
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getADot
public T getADot()
Get the semi-major axis derivative.Note that the semi-major axis is considered negative for hyperbolic orbits.
If the orbit was created without derivatives, the value returned is null.
- Specified by:
getADotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- semi-major axis derivative (m/s)
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getE
public T getE()
Get the eccentricity.- Specified by:
getEin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- eccentricity
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getEDot
public T getEDot()
Get the eccentricity derivative.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getEDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- eccentricity derivative
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getI
public T getI()
Get the inclination.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getIin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- inclination (rad)
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getIDot
public T getIDot()
Get the inclination derivative.- Specified by:
getIDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- inclination derivative (rad/s)
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getPerigeeArgument
public T getPerigeeArgument()
Get the perigee argument.- Returns:
- perigee argument (rad)
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getPerigeeArgumentDot
public T getPerigeeArgumentDot()
Get the perigee argument derivative.If the orbit was created without derivatives, the value returned is null.
- Returns:
- perigee argument derivative (rad/s)
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getRightAscensionOfAscendingNode
public T getRightAscensionOfAscendingNode()
Get the right ascension of the ascending node.- Returns:
- right ascension of the ascending node (rad)
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getRightAscensionOfAscendingNodeDot
public T getRightAscensionOfAscendingNodeDot()
Get the right ascension of the ascending node derivative.If the orbit was created without derivatives, the value returned is null.
- Returns:
- right ascension of the ascending node derivative (rad/s)
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getTrueAnomaly
public T getTrueAnomaly()
Get the true anomaly.- Returns:
- true anomaly (rad)
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getTrueAnomalyDot
public T getTrueAnomalyDot()
Get the true anomaly derivative.If the orbit was created without derivatives, the value returned is null.
- Returns:
- true anomaly derivative (rad/s)
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getEccentricAnomaly
public T getEccentricAnomaly()
Get the eccentric anomaly.- Returns:
- eccentric anomaly (rad)
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getEccentricAnomalyDot
public T getEccentricAnomalyDot()
Get the eccentric anomaly derivative.If the orbit was created without derivatives, the value returned is null.
- Returns:
- eccentric anomaly derivative (rad/s)
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getMeanAnomaly
public T getMeanAnomaly()
Get the mean anomaly.- Returns:
- mean anomaly (rad)
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getMeanAnomalyDot
public T getMeanAnomalyDot()
Get the mean anomaly derivative.If the orbit was created without derivatives, the value returned is null.
- Returns:
- mean anomaly derivative (rad/s)
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getAnomaly
public T getAnomaly(PositionAngleType type)
Get the anomaly.- Parameters:
type- type of the angle- Returns:
- anomaly (rad)
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getAnomalyDot
public T getAnomalyDot(PositionAngleType type)
Get the anomaly derivative.If the orbit was created without derivatives, the value returned is null.
- Parameters:
type- type of the angle- Returns:
- anomaly derivative (rad/s)
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hasDerivatives
public boolean hasDerivatives()
Check if orbit includes derivatives.- Specified by:
hasDerivativesin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- true if orbit includes derivatives
- See Also:
FieldOrbit.getADot(),FieldOrbit.getEquinoctialExDot(),FieldOrbit.getEquinoctialEyDot(),FieldOrbit.getHxDot(),FieldOrbit.getHyDot(),FieldOrbit.getLEDot(),FieldOrbit.getLvDot(),FieldOrbit.getLMDot(),FieldOrbit.getEDot(),FieldOrbit.getIDot()
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getEquinoctialEx
public T getEquinoctialEx()
Get the first component of the equinoctial eccentricity vector.- Specified by:
getEquinoctialExin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- first component of the equinoctial eccentricity vector
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getEquinoctialExDot
public T getEquinoctialExDot()
Get the first component of the equinoctial eccentricity vector.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getEquinoctialExDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- first component of the equinoctial eccentricity vector
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getEquinoctialEy
public T getEquinoctialEy()
Get the second component of the equinoctial eccentricity vector.- Specified by:
getEquinoctialEyin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- second component of the equinoctial eccentricity vector
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getEquinoctialEyDot
public T getEquinoctialEyDot()
Get the second component of the equinoctial eccentricity vector.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getEquinoctialEyDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- second component of the equinoctial eccentricity vector
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getHx
public T getHx()
Get the first component of the inclination vector.- Specified by:
getHxin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- first component of the inclination vector
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getHxDot
public T getHxDot()
Get the first component of the inclination vector derivative.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getHxDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- first component of the inclination vector derivative
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getHy
public T getHy()
Get the second component of the inclination vector.- Specified by:
getHyin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- second component of the inclination vector
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getHyDot
public T getHyDot()
Get the second component of the inclination vector derivative.- Specified by:
getHyDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- second component of the inclination vector derivative
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getLv
public T getLv()
Get the true longitude argument.- Specified by:
getLvin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- v + ω + Ω true longitude argument (rad)
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getLvDot
public T getLvDot()
Get the true longitude argument derivative.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getLvDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- d(v + ω + Ω)/dt true longitude argument derivative (rad/s)
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getLE
public T getLE()
Get the eccentric longitude argument.- Specified by:
getLEin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- E + ω + Ω eccentric longitude argument (rad)
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getLEDot
public T getLEDot()
Get the eccentric longitude argument derivative.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getLEDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- d(E + ω + Ω)/dt eccentric longitude argument derivative (rad/s)
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getLM
public T getLM()
Get the mean longitude argument.- Specified by:
getLMin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- M + ω + Ω mean longitude argument (rad)
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getLMDot
public T getLMDot()
Get the mean longitude argument derivative.If the orbit was created without derivatives, the value returned is null.
- Specified by:
getLMDotin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- d(M + ω + Ω)/dt mean longitude argument derivative (rad/s)
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initPosition
protected FieldVector3D<T> initPosition()
Compute the position coordinates from the canonical parameters.- Specified by:
initPositionin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- computed position coordinates
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initPVCoordinates
protected TimeStampedFieldPVCoordinates<T> initPVCoordinates()
Compute the position/velocity coordinates from the canonical parameters.- Specified by:
initPVCoordinatesin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- computed position/velocity coordinates
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shiftedBy
public FieldKeplerianOrbit<T> shiftedBy(double dt)
Get a time-shifted instance.- Specified by:
shiftedByin interfaceTimeShiftable<T extends CalculusFieldElement<T>>- Parameters:
dt- time shift in seconds- Returns:
- a new instance, shifted with respect to instance (which is not changed)
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shiftedBy
public FieldKeplerianOrbit<T> shiftedBy(T dt)
Get a time-shifted orbit.The orbit can be slightly shifted to close dates. This shift is based on a simple Keplerian model. It is not intended as a replacement for proper orbit and attitude propagation but should be sufficient for small time shifts or coarse accuracy.
- Specified by:
shiftedByin interfaceFieldTimeShiftable<FieldOrbit<T extends CalculusFieldElement<T>>,T extends CalculusFieldElement<T>>- Specified by:
shiftedByin classFieldOrbit<T extends CalculusFieldElement<T>>- Parameters:
dt- time shift in seconds- Returns:
- a new orbit, shifted with respect to the instance (which is immutable)
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computeJacobianMeanWrtCartesian
protected T[][] computeJacobianMeanWrtCartesian()
Compute the Jacobian of the orbital parameters with mean angle with respect to the Cartesian parameters.Element
jacobian[i][j]is the derivative of parameter i of the orbit with respect to Cartesian coordinate j. This means each row correspond to one orbital parameter whereas columns 0 to 5 correspond to the Cartesian coordinates x, y, z, xDot, yDot and zDot.- Specified by:
computeJacobianMeanWrtCartesianin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- 6x6 Jacobian matrix
- See Also:
FieldOrbit.computeJacobianEccentricWrtCartesian(),FieldOrbit.computeJacobianTrueWrtCartesian()
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computeJacobianEccentricWrtCartesian
protected T[][] computeJacobianEccentricWrtCartesian()
Compute the Jacobian of the orbital parameters with eccentric angle with respect to the Cartesian parameters.Element
jacobian[i][j]is the derivative of parameter i of the orbit with respect to Cartesian coordinate j. This means each row correspond to one orbital parameter whereas columns 0 to 5 correspond to the Cartesian coordinates x, y, z, xDot, yDot and zDot.- Specified by:
computeJacobianEccentricWrtCartesianin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- 6x6 Jacobian matrix
- See Also:
FieldOrbit.computeJacobianMeanWrtCartesian(),FieldOrbit.computeJacobianTrueWrtCartesian()
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computeJacobianTrueWrtCartesian
protected T[][] computeJacobianTrueWrtCartesian()
Compute the Jacobian of the orbital parameters with true angle with respect to the Cartesian parameters.Element
jacobian[i][j]is the derivative of parameter i of the orbit with respect to Cartesian coordinate j. This means each row correspond to one orbital parameter whereas columns 0 to 5 correspond to the Cartesian coordinates x, y, z, xDot, yDot and zDot.- Specified by:
computeJacobianTrueWrtCartesianin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- 6x6 Jacobian matrix
- See Also:
FieldOrbit.computeJacobianMeanWrtCartesian(),FieldOrbit.computeJacobianEccentricWrtCartesian()
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addKeplerContribution
public void addKeplerContribution(PositionAngleType type, T gm, T[] pDot)
Add the contribution of the Keplerian motion to parameters derivativesThis method is used by integration-based propagators to evaluate the part of Keplerian motion to evolution of the orbital state.
- Specified by:
addKeplerContributionin classFieldOrbit<T extends CalculusFieldElement<T>>- Parameters:
type- type of the position angle in the stategm- attraction coefficient to usepDot- array containing orbital state derivatives to update (the Keplerian part must be added to the array components, as the array may already contain some non-zero elements corresponding to non-Keplerian parts)
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toString
public String toString()
Returns a string representation of this Keplerian parameters object.
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getCachedPositionAngleType
public PositionAngleType getCachedPositionAngleType()
Get the cachedPositionAngleType.- Specified by:
getCachedPositionAngleTypein interfacePositionAngleBased- Returns:
- cached type of position angle
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hasRates
public boolean hasRates()
Tells whether the instance holds rates (first-order time derivatives) for dependent variables.- Specified by:
hasRatesin interfacePositionAngleBased- Returns:
- true if and only if holding rates
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removeRates
public FieldKeplerianOrbit<T> removeRates()
Create a new instance such thatPositionAngleBased.hasRates()is false.- Specified by:
removeRatesin interfacePositionAngleBased- Returns:
- new object without rates
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toOrbit
public KeplerianOrbit toOrbit()
Transforms the FieldOrbit instance into an Orbit instance.- Specified by:
toOrbitin classFieldOrbit<T extends CalculusFieldElement<T>>- Returns:
- Orbit instance with same properties
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