Keplerian orbital elements, for example, for a comet using parameters published by the IAU Minor Planet Center. More...

#include <supernovas.h>

Inheritance diagram for supernovas::Orbital:

Public Member Functions
	Orbital (const OrbitalSystem &system, const Time &ref_time, const Coordinate &semi_major, const Angle &mean_anomaly, const Interval &period)
	Instantiates a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters.
	Orbital (const OrbitalSystem &system, double jd_tdb, double semi_major_m, double mean_anomaly_rad, double period_s)
	Instantiates a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters.
const novas_orbital *	_novas_orbital () const
	(for internal use) Returns the underlying NOVAS C data structure containing the orbital parameters.
Interval	apsis_period () const
	Returns the rotation period of the apsis location in the orbital system, in which the orbital was defined (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).
Orbital &	apsis_period (const Interval &period)
	Sets the apsis rotation period (positive for counter-clockwise rotation when viewed from the orbital system's pole).
Orbital &	apsis_period (double seconds)
	Sets the apsis rotation period (positive for counter-clockwise rotation when viewed from the orbital system's pole).
double	apsis_rate () const
	Returns the angular rate at which the apsis rotates in the orbital system (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).
Orbital &	apsis_rate (double rad_per_sec)
	Sets the apsis rotation rate (positive for counter-clockwise rotation when viewed from the orbital system's pole).
Angle	ascending_node () const
	Returns the longitude of the ascending node of this orbit in the orbital system, in which the orbital was defined.
double	eccentricity () const
	Returns the eccentricity of this orbital.
Orbital &	eccentricity (double e, const Angle &periapsis_angle)
	Sets parameters for an elliptical orbit.
Orbital &	eccentricity (double e, double periapsis_rad)
	Sets parameters for an elliptical orbit.
Angle	inclination () const
	Returns the inclination angle of this orbit, relative to the orbital system's plane.
Orbital &	inclination (const Angle &angle, const Angle &ascending_node_angle)
	Sets parameters for an orbit that is inclined relative to the orbital system's native plane.
Orbital &	inclination (double angle_rad, double ascending_node_rad)
	Sets parameters for an orbit that is inclined relative to the orbital system's native plane.
double	mean_motion () const
	Returns the mean motion (circular angular velocity) of the object in this orbit.
Interval	node_period () const
	Returns the rotation period (due to precession) of the orbit's ascending node in the orbital system, in which the orbital was defined (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).
Orbital &	node_period (const Interval &period)
	Sets the node precession period (positive for counter-clockwise rotation when viewed from the orbital system's pole).
Orbital &	node_period (double seconds)
	Sets the node precession period (positive for counter-clockwise rotation when viewed from the orbital system's pole).
double	node_rate () const
	Returns the angular rate at which the ascending node of the orbit rotates in the orbital system (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).
Orbital &	node_rate (double rad_per_sec)
	Sets the node precession rate (positive for counter-clockwise rotation when viewed from the orbital system's pole).
Angle	periapsis () const
	Returns the periapsis angle of this orbit, in the orbital system, in which the orbit was defined.
Interval	period () const
	Returns the period of the object on this orbit.
Spherical	pole () const
	Returns the spherical coordinates of the orbit's pole in the orbital system, in which the orbital was defined.
Orbital &	pole (const Angle &longitude, const Angle &latitude)
	Sets the orbit's pole, in the orbital system in which the orbit is defined.
Orbital &	pole (const Spherical &coords)
	Sets the orbit's pole, in the orbital system in which the orbit is defined.
Orbital &	pole (double longitude_rad, double latitude_rad)
	Sets the orbit's pole, in the orbital system in which the orbit is defined.
Position	position (const Time &time, enum novas_accuracy accuracy=NOVAS_FULL_ACCURACY) const
	Calculates a rectangular equatorial position vector for this Keplerian orbital for the specified time of observation.
double	reference_jd_tdb () const
	Returns the reference time, as a Barycentric Dynamical Time (TDB) based Julian date.
Angle	reference_mean_anomaly () const
	Returns the mean anomaly (or longitude for circular orbits) of the object at the reference time, in the orbital system in which the orbit was defined.
Coordinate	semi_major_axis () const
	Returns the semi-major axis (that is the radius for circular orbits) of this orbital.
OrbitalSystem	system () const
	Returns a new instance of the orbital system in which this orbit is defined.
OrbitalSource	to_source (const std::string &name) const
	Returns a new orbital source from this orbital and with the specified name and number designations.
std::string	to_string () const
	Returns a basic human-readable description of this orbital, with just the major parameters.
Velocity	velocity (const Time &time, enum novas_accuracy accuracy=NOVAS_FULL_ACCURACY) const
	Calculates a rectangular equatorial velocity vector for this Keplerian orbital for the specified time of observation.
Public Member Functions inherited from supernovas::Validating
bool	is_valid () const
	Returns the previously set 'valid' stae of the implementing instance.
	operator bool () const
	Objects that implement Validating can be used in conditionals directly, without explicitly calling is_valid().

Static Public Member Functions
static Orbital	from_mean_motion (const OrbitalSystem &system, const Time &ref_time, const Coordinate &semi_major, const Angle &mean_anomaly, double rad_per_s)
	Return a new instance of a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters, with mean motion used instead of a orbital period.
static Orbital	from_mean_motion (const OrbitalSystem &system, double jd_tdb, double semi_majpr_m, double mean_anomaly_rad, double rad_per_s)
	Return a new instance of a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters, with mean motion used instead of a orbital period.
static Orbital	from_novas_orbit (const novas_orbital *orbit)
	(for internal use) Returns a new instance of a Keplerian orbital, using a copy of a NOVAS C orbital data structure, or std::nullopt if the argument is NULL.
static Orbital	moon_mean_orbit_at (const Time &time)
	Returns the mean Keplerian orbital for the Moon relative to the geocenter for the specified epoch of observation.
static Orbital	moon_orbit_at (const Time &time)
	Returns an approximation of the current Keplerian orbital of the Moon relative to the geocenter for the specified epoch of observation.

Additional Inherited Members
Protected Member Functions inherited from supernovas::Validating
	Validating ()
	dummy constructor;
Protected Attributes inherited from supernovas::Validating
bool	_valid = false
	the state variable.

Detailed Description

Keplerian orbital elements, for example, for a comet using parameters published by the IAU Minor Planet Center.

While Keplerian orbitals cannot provide accurate positions or velocities for Solar-system bodies over the long term (for that you need ephemeris data), they can be sufficiently accurate on the short term. And, in case of recently discovered objects, such as Near-Earth Objects (NEOs), orbital elements may be the only source of up-to-date positional data.

NOTES:

This class uses a builder pattern to populate the orbital parameters, bit-by-bit, as needed. As such, this class is mutable, unlike most SuperNOVAS classes. You should avoid using the builder functions in a multi-threaded environment. The best practice is to build the orbital first, before using in parallel threads unmodified.

See also: EphemerisSource, Planet::orbit()

Constructor & Destructor Documentation

◆ Orbital() [1/2]

supernovas::Orbital::Orbital	(	const OrbitalSystem &	system,
		double	jd_tdb,
		double	semi_major_m,
		double	mean_anomaly_rad,
		double	period_s )

Instantiates a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters.

You can further specify the parameters for elliptical orbits using a builder pattern after instantiation.

Parameters

system	the orbital system in which the orbit is defined.
jd_tdb	[day] reference date of the orbital parameters as a Barycentric Dynamical Time (TDB) based Julian date
semi_major_m	[m] semi-major axis (circular radius) of the orbit
mean_anomaly_rad	[rad] Mean anomaly (circular longitude) of the object at the reference time, in the orbital system.
period_s	[s] orbital period.

See also: OribtalSystem::orbit(); from_mean_motion(), eccentricity(), inclination(), pole(), node_period(), node_rate() apsis_period(), apsis_rate()

References supernovas::Unit::au, supernovas::Unit::day, supernovas::Unit::deg, and system().

◆ Orbital() [2/2]

supernovas::Orbital::Orbital	(	const OrbitalSystem &	system,
		const Time &	ref_time,
		const Coordinate &	semi_major,
		const Angle &	mean_anomaly,
		const Interval &	period )

Instantiates a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters.

You can further specify the parameters for elliptical orbits using a builder pattern after instantiation.

Parameters

system	the orbital system in which the orbit is defined.
ref_time	reference time of the orbital parameters.
semi_major	semi-major axis (circular radius) of the orbit
mean_anomaly	Mean anomaly (circular longitude) of the object at the reference time, in the orbital system.
period	orbital period.

See also: OrbotalSystem::orbit(); from_mean_motion(), eccentricity(), inclination(), pole(), node_period(), node_rate() apsis_period(), apsis_rate()

References NOVAS_TDB, period(), and system().

Member Function Documentation

◆ _novas_orbital()

const novas_orbital * supernovas::Orbital::_novas_orbital ( ) const

(for internal use) Returns the underlying NOVAS C data structure containing the orbital parameters.

Returns: pointer to the NOVAS C data structure that stores the orbital parameters internally.

Referenced by supernovas::OrbitalSource::OrbitalSource().

◆ apsis_period() [1/3]

Interval supernovas::Orbital::apsis_period ( ) const

Returns the rotation period of the apsis location in the orbital system, in which the orbital was defined (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).

Returns: the time it takes for the apsis to make a full counter-clockwise rotation in the orbital system, viewed from the orbital system's pole. It may be negative for retrograde (clockwise) motion.

See also: apsis_rate(), eccentricity(), node_period()

References supernovas::Unit::day, and supernovas::Validating::is_valid().

Referenced by apsis_period(), apsis_rate(), and apsis_rate().

◆ apsis_period() [2/3]

Orbital & supernovas::Orbital::apsis_period ( const Interval & period )

Sets the apsis rotation period (positive for counter-clockwise rotation when viewed from the orbital system's pole).

Parameters

period time it takes for a full rotation of the apsis in the orbital system. It may be negative for clockwise (retrograde) rotation seen from the orbital system's pole.

Returns: itself

See also: apsis_rate(), periapsis(), eccentricity()

References apsis_period(), and period().

◆ apsis_period() [3/3]

Orbital & supernovas::Orbital::apsis_period ( double seconds )

Sets the apsis rotation period (positive for counter-clockwise rotation when viewed from the orbital system's pole).

Parameters

seconds [s] counter-clockwise rotation period of the apsis. It may be negative for clockwise (retrograde) rotation seen from the orbital system's pole.

Returns: itself

See also: apsis_rate(), periapsis(), eccentricity()

References supernovas::Validating::_valid, and supernovas::Unit::day.

◆ apsis_rate() [1/2]

double supernovas::Orbital::apsis_rate ( ) const

Returns the angular rate at which the apsis rotates in the orbital system (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).

Returns: [rad/s] the angular velocity of the apsis' rotation in the orbital system, viewed from the orbital system's pole. It may be negative for retrograde motion.

See also: apsis_period(), node_rate()

References apsis_period(), and supernovas::Constant::two_pi.

◆ apsis_rate() [2/2]

Orbital & supernovas::Orbital::apsis_rate ( double rad_per_sec )

Sets the apsis rotation rate (positive for counter-clockwise rotation when viewed from the orbital system's pole).

Parameters

rad_per_sec [rad/s] counter-clockwise rotation rate of the apsis. It may be negative for clockwise (retrograde) rotation seen from the orbital system's pole.

Returns: itself

See also: apsis_rate(), periapsis(), eccentricity()

References apsis_period(), and supernovas::Constant::two_pi.

◆ ascending_node()

Angle supernovas::Orbital::ascending_node ( ) const

Returns the longitude of the ascending node of this orbit in the orbital system, in which the orbital was defined.

Returns: the longitude of the ascending node in the orbital system.

See also: inclination(), pole()

References supernovas::Unit::deg, and supernovas::Validating::is_valid().

◆ eccentricity() [1/3]

double supernovas::Orbital::eccentricity ( ) const

Returns the eccentricity of this orbital.

Returns: the eccentricity of this orbital (dimensionless).

See also: periapsis()

Referenced by eccentricity(), and to_string().

◆ eccentricity() [2/3]

Orbital & supernovas::Orbital::eccentricity	(	double	e,
		const Angle &	periapsis_angle )

Sets parameters for an elliptical orbit.

Parameters

e	eccenticity value (dimensionless).
periapsis_angle	longitude of the apsis (the point at which the elliptial orbit is closest to the center), in the orbital system, in which the orbit is defined.

Returns: itself.

See also: apsis_period(), apsis_rate()

References eccentricity(), and supernovas::Angle::rad().

◆ eccentricity() [3/3]

Orbital & supernovas::Orbital::eccentricity	(	double	e,
		double	periapsis_rad )

Sets parameters for an elliptical orbit.

Parameters

e	eccenticity value (dimensionless).
periapsis_rad	[rad] longitude of the apsis (the point at which the elliptial orbit is closest to the center), in the orbital system, in which the orbit is defined.

Returns: itself.

See also: apsis_period(), apsis_rate()

References supernovas::Validating::_valid, and supernovas::Unit::deg.

◆ from_mean_motion() [1/2]

Orbital supernovas::Orbital::from_mean_motion	(	const OrbitalSystem &	system,
		const Time &	ref_time,
		const Coordinate &	semi_major,
		const Angle &	mean_anomaly,
		double	rad_per_sec )

static

Return a new instance of a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters, with mean motion used instead of a orbital period.

You can further specify the parameters for elliptical orbits using a builder pattern after instantiation.

Parameters

system	the orbital system in which the orbit is defined.
ref_time	reference time of the orbital parameters.
semi_major	semi-major axis (circular radius; a) of the orbit
mean_anomaly	Mean anomaly (circular longitude; M0) of the object at the reference time, in the orbital system.
rad_per_sec	[rad/s] mean motion (circular angular velocity) on orbit.

See also: Orbital(), eccentricity(), inclination(), pole(), node_period(), node_rate() apsis_period(), apsis_rate()

References from_mean_motion(), supernovas::Time::jd(), supernovas::Coordinate::m(), NOVAS_TDB, supernovas::Angle::rad(), and system().

◆ from_mean_motion() [2/2]

Orbital supernovas::Orbital::from_mean_motion	(	const OrbitalSystem &	system,
		double	jd_tdb,
		double	semi_major_m,
		double	mean_anomaly_rad,
		double	rad_per_sec )

static

Return a new instance of a new Keplerian orbital in the specified orbital system and the basic circular orbital parameters, with mean motion used instead of a orbital period.

You can further specify the parameters for elliptical orbits using a builder pattern after instantiation.

Parameters

system	the orbital system in which the orbit is defined.
jd_tdb	[day] reference date of the orbital parameters as a Barycentric Dynamical Time (TDB) based Julian date
semi_major_m	[m] semi-major axis (circular radius; a) of the orbit
mean_anomaly_rad	[rad] Mean anomaly (circular longitude; M0) of the object at the reference time, in the orbital system.
rad_per_sec	[rad/s] mean motion (circular angular velocity) on orbit.

See also: Orbital(), eccentricity(), inclination(), pole(), node_period(), node_rate() apsis_period(), apsis_rate()

References supernovas::Validating::is_valid(), system(), and supernovas::Constant::two_pi.

Referenced by from_mean_motion().

◆ from_novas_orbit()

Orbital supernovas::Orbital::from_novas_orbit ( const novas_orbital * orbit )

static

(for internal use) Returns a new instance of a Keplerian orbital, using a copy of a NOVAS C orbital data structure, or std::nullopt if the argument is NULL.

It's best practice to call is_valid() after to check that the supplied parameters do in fact define a valid orbital system.

Parameters

orbit The NOVAS C orbital data structure (copied)

Returns: A new Keplerian orbital instance, with the specified parameters.

See also: Orbital(), is_valid()

References supernovas::Validating::is_valid().

Referenced by moon_mean_orbit_at(), moon_orbit_at(), supernovas::Planet::orbit(), and supernovas::OrbitalSource::orbital().

◆ inclination() [1/3]

Angle supernovas::Orbital::inclination ( ) const

Returns the inclination angle of this orbit, relative to the orbital system's plane.

Returns: the inclination of the orbit relative to the orbital system's plane.

See also: ascending_node(), pole()

References supernovas::Unit::deg, and supernovas::Validating::is_valid().

Referenced by inclination(), and pole().

◆ inclination() [2/3]

Orbital & supernovas::Orbital::inclination	(	const Angle &	angle,
		const Angle &	ascending_node_angle )

Sets parameters for an orbit that is inclined relative to the orbital system's native plane.

Parameters

angle	inclination angle
ascending_node_angle	longitude of the ascending node in the orbital system, in which the orbit is defined.

Returns: itself.

See also: pole(), node_period(), node_rate()

References inclination(), and supernovas::Angle::rad().

◆ inclination() [3/3]

Orbital & supernovas::Orbital::inclination	(	double	angle_rad,
		double	ascending_node_rad )

Sets parameters for an orbit that is inclined relative to the orbital system's native plane.

Parameters

angle_rad	[rad] inclination angle
ascending_node_rad	[rad] longitude of the ascending node in the orbital system, in which the orbit is defined.

Returns: itself.

See also: pole(), node_period(), node_rate()

References supernovas::Validating::_valid, and supernovas::Unit::deg.

◆ mean_motion()

double supernovas::Orbital::mean_motion ( ) const

Returns the mean motion (circular angular velocity) of the object in this orbit.

Returns: [rad/s] the mean motion (circular angular velocity) of the object on this orbit.

See also: period()

References supernovas::Unit::day, and supernovas::Unit::deg.

Referenced by period().

◆ moon_mean_orbit_at()

Orbital supernovas::Orbital::moon_mean_orbit_at ( const Time & time )

static

Returns the mean Keplerian orbital for the Moon relative to the geocenter for the specified epoch of observation.

It is based on the secular parameters of the ELP2000-85 model, but does not include the harmonic series and the perturbation terms. As such it has accuracy at the few degrees level only, however it is 'valid' for long-term projections (i.e. for years around the orbit's reference epoch) at that coarse level.

For the short-term , Orbital::moon_orbit_at() can provide somewhat more accurate predictions for up to a day or so around the reference epoch of the orbit.

REFERENCES:

Chapront, J. et al., 2002, A&A 387, 700–709
Chapront-Touze, M, and Chapront, J. 1988, Astronomy and Astrophysics, vol. 190, p. 342-352.
Chapront J., Francou G., 2003, A&A, 404, 735
Laskar J., 1986, A&A, 157, 59

Parameters

Time of observation and astronomical timescales Astrometric time for which to calculate the secular orbital parameters of the moon.

Returns: the Moon orbital defined with the mean orbital elements of date.

See also: moon_orbit_at()

References from_novas_orbit(), supernovas::Validating::is_valid(), supernovas::Time::jd(), novas_make_moon_mean_orbit(), and NOVAS_TDB.

◆ moon_orbit_at()

Orbital supernovas::Orbital::moon_orbit_at ( const Time & time )

static

Returns an approximation of the current Keplerian orbital of the Moon relative to the geocenter for the specified epoch of observation.

The orbit includes the most dominant Solar perturbation terms to produce results with an accuracy at the ~10 arcmin level near (+- 0.5 days) the reference time argument of the orbit. The perturbed orbit is based on the ELP/MPP02 model.

While, the ELP/MPP02 model itself can be highly precise, the Moon's orbit is strongly non-Keplerian, and so any attempt to describe it in purely Keplerian terms is inherently flawed, which is the reason for the generally poor accuracy of this model.

REFERENCES:

Chapront, J. et al., 2002, A&A 387, 700–709
Chapront-Touze, M, and Chapront, J. 1988, Astronomy and Astrophysics, vol. 190, p. 342-352.
Chapront J., Francou G., 2003, A&A, 404, 735

Parameters

Time of observation and astronomical timescales Astrometric time for which to calculate the secular orbital parameters of the moon.

Returns: the Moon orbital defined with the mean orbital elements of date.

See also: moon_mean_orbit_at()

References from_novas_orbit(), supernovas::Validating::is_valid(), supernovas::Time::jd(), novas_make_moon_orbit(), and NOVAS_TDB.

◆ node_period() [1/3]

Interval supernovas::Orbital::node_period ( ) const

Returns the rotation period (due to precession) of the orbit's ascending node in the orbital system, in which the orbital was defined (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).

Returns: the time it takes for the ascending to make a full counter-clockwise rotation in the orbital system, viewed from the orbital system's pole. It may be negative for retrograde (clockwise) motion.

See also: node_rate(), inclination(), apsis_period()

References supernovas::Unit::day, and supernovas::Validating::is_valid().

Referenced by node_period(), node_rate(), and node_rate().

◆ node_period() [2/3]

Orbital & supernovas::Orbital::node_period ( const Interval & period )

Sets the node precession period (positive for counter-clockwise rotation when viewed from the orbital system's pole).

Parameters

period counter-clockwise precession period of the node. It may be negative for clockwise (retrograde) rotation seen from the orbital system's pole.

Returns: itself

See also: node_rate(), ascending_node(), inclination(), pole()

References node_period(), and period().

◆ node_period() [3/3]

Orbital & supernovas::Orbital::node_period ( double seconds )

Sets the node precession period (positive for counter-clockwise rotation when viewed from the orbital system's pole).

Parameters

seconds [s] counter-clockwise precession period of the node. It may be negative for clockwise (retrograde) rotation seen from the orbital system's pole.

Returns: itself

See also: node_rate(), ascending_node(), inclination(), pole()

References supernovas::Validating::_valid, and supernovas::Unit::day.

◆ node_rate() [1/2]

double supernovas::Orbital::node_rate ( ) const

Returns the angular rate at which the ascending node of the orbit rotates in the orbital system (positive for counter-clockwise rotation, or negative for clockwise rotation, when viewed from the orbital system's pole.).

Returns: [rad/s] the angular velocity of the ascending node rotation (precession) in the orbital system, viewed from the orbital system's pole. It may be negative for retrograde motion.

See also: node_period(), apsis_rate()

References node_period(), and supernovas::Constant::two_pi.

◆ node_rate() [2/2]

Orbital & supernovas::Orbital::node_rate ( double rad_per_sec )

Sets the node precession rate (positive for counter-clockwise rotation when viewed from the orbital system's pole).

Parameters

rad_per_sec [rad/sec] counter-clockwise precession rate of the node. It may be negative for clockwise (retrograde) rotation seen from the orbital system's pole.

Returns: itself

See also: node_period(), ascending_node(), inclination(), pole()

References node_period(), and supernovas::Constant::two_pi.

◆ periapsis()

Angle supernovas::Orbital::periapsis ( ) const

Returns the periapsis angle of this orbit, in the orbital system, in which the orbit was defined.

Returns: the longitude (in the orbital system) at which point the object is closest to the orbital center (on an elliptical orbit).

See also: eccentricity()

References supernovas::Unit::deg, and supernovas::Validating::is_valid().

◆ period()

Interval supernovas::Orbital::period ( ) const

Returns the period of the object on this orbit.

Returns: the time it takes for the object to complete a full orbit.

See also: mean_motion()

References supernovas::Validating::is_valid(), mean_motion(), and supernovas::Constant::two_pi.

Referenced by Orbital(), apsis_period(), node_period(), and to_string().

◆ pole() [1/4]

Spherical supernovas::Orbital::pole ( ) const

Returns the spherical coordinates of the orbit's pole in the orbital system, in which the orbital was defined.

Returns: the location of the orbit's pole in the orbital system, in which the orbital is defined.

See also: inclination(), ascending_node()

References supernovas::Unit::deg, supernovas::Constant::half_pi, and supernovas::Validating::is_valid().

Referenced by pole(), and pole().

◆ pole() [2/4]

Orbital & supernovas::Orbital::pole	(	const Angle &	longitude,
		const Angle &	latitude )

Sets the orbit's pole, in the orbital system in which the orbit is defined.

Parameters

longitude	longitude of orbit's pole in the orbital system.
latitude	latitude of the orbit's pole in the orbital system.

Returns: itself

See also: inclination(), node_pediod(), node_rate()

References pole(), and supernovas::Angle::rad().

◆ pole() [3/4]

Orbital & supernovas::Orbital::pole ( const Spherical & coords )

Sets the orbit's pole, in the orbital system in which the orbit is defined.

Parameters

coords location of the pole in the orbital system.

Returns: itself

See also: inclination(), node_pediod(), node_rate()

References supernovas::Spherical::latitude(), supernovas::Spherical::longitude(), and pole().

◆ pole() [4/4]

Orbital & supernovas::Orbital::pole	(	double	longitude_rad,
		double	latitude_rad )

Sets the orbit's pole, in the orbital system in which the orbit is defined.

Parameters

longitude_rad	[rad] longitude of orbit's pole in the orbital system.
latitude_rad	[rad] latitude of the orbit's pole in the orbital system.

Returns: itself

See also: inclination(), node_pediod(), node_rate()

References supernovas::Constant::half_pi, and inclination().

◆ position()

Position supernovas::Orbital::position	(	const Time &	time,
		enum novas_accuracy	accuracy = NOVAS_FULL_ACCURACY ) const

Calculates a rectangular equatorial position vector for this Keplerian orbital for the specified time of observation.

REFERENCES:

E.M. Standish and J.G. Williams 1992.
https://ssd.jpl.nasa.gov/planets/approx_pos.html
https://en.wikipedia.org/wiki/Orbital_elements
https://orbitalofficial.com/
https://downloads.rene-schwarz.com/download/M001-Keplerian_Orbit_Elements_to_Cartesian_State_Vectors.pdf

Parameters

Time of observation and astronomical timescales	Astrometric time of observation
accuracy	NOVAS_FULL_ACCURACY (0) or NOVAS_REDUCED_ACCURACY (1).

Returns: The rectangular equatorial position vector of the orbital object, relative to the equinox type of the orbital system.

See also: velocity()

References supernovas::Unit::au, supernovas::Time::jd(), novas_orbit_posvel(), and supernovas::Position::undefined().

◆ reference_jd_tdb()

double supernovas::Orbital::reference_jd_tdb ( ) const

Returns the reference time, as a Barycentric Dynamical Time (TDB) based Julian date.

Returns: [day] the TDB-based Julian date for which the orbital parameters are defined.

◆ reference_mean_anomaly()

Angle supernovas::Orbital::reference_mean_anomaly ( ) const

Returns the mean anomaly (or longitude for circular orbits) of the object at the reference time, in the orbital system in which the orbit was defined.

Returns: the mean anomaly (circular longitude) of the object in the orbital system at the reference time.

See also: reference_jd_tdb()

References supernovas::Unit::deg, and supernovas::Validating::is_valid().

◆ semi_major_axis()

Coordinate supernovas::Orbital::semi_major_axis ( ) const

Returns the semi-major axis (that is the radius for circular orbits) of this orbital.

Returns: the semi-major axis (circular) radius of this orbit.

References supernovas::Unit::au, and supernovas::Validating::is_valid().

Referenced by to_string().

◆ system()

OrbitalSystem supernovas::Orbital::system ( ) const

Returns a new instance of the orbital system in which this orbit is defined.

Returns: a new instance of the orbital system, in which the orbit is defined.

References supernovas::OrbitalSystem::from_novas_orbital_system(), and supernovas::Validating::is_valid().

Referenced by Orbital(), Orbital(), from_mean_motion(), from_mean_motion(), and to_string().

◆ to_string()

std::string supernovas::Orbital::to_string ( ) const

Returns a basic human-readable description of this orbital, with just the major parameters.

Returns: a basic string description of this orbital.

References eccentricity(), period(), semi_major_axis(), system(), supernovas::Coordinate::to_string(), supernovas::Interval::to_string(), and supernovas::OrbitalSystem::to_string().

◆ velocity()

Velocity supernovas::Orbital::velocity	(	const Time &	time,
		enum novas_accuracy	accuracy = NOVAS_FULL_ACCURACY ) const

Calculates a rectangular equatorial velocity vector for this Keplerian orbital for the specified time of observation.

REFERENCES:

E.M. Standish and J.G. Williams 1992.
https://ssd.jpl.nasa.gov/planets/approx_pos.html
https://en.wikipedia.org/wiki/Orbital_elements
https://orbitalofficial.com/
https://downloads.rene-schwarz.com/download/M001-Keplerian_Orbit_Elements_to_Cartesian_State_Vectors.pdf

Parameters

Time of observation and astronomical timescales	Astrometric time of observation
accuracy	NOVAS_FULL_ACCURACY (0) or NOVAS_REDUCED_ACCURACY (1).

Returns: The rectangular equatorial velocity vector of the orbital object, relative to the equinox type of the orbital system.

See also: position()

References supernovas::Unit::au, supernovas::Unit::day, supernovas::Time::jd(), novas_orbit_posvel(), and supernovas::Velocity::undefined().

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Orbital() [1/2]

◆ Orbital() [2/2]

Member Function Documentation

◆ _novas_orbital()

◆ apsis_period() [1/3]

◆ apsis_period() [2/3]

◆ apsis_period() [3/3]

◆ apsis_rate() [1/2]

◆ apsis_rate() [2/2]

◆ ascending_node()

◆ eccentricity() [1/3]

◆ eccentricity() [2/3]

◆ eccentricity() [3/3]

◆ from_mean_motion() [1/2]

◆ from_mean_motion() [2/2]

◆ from_novas_orbit()

◆ inclination() [1/3]

◆ inclination() [2/3]

◆ inclination() [3/3]

◆ mean_motion()

◆ moon_mean_orbit_at()

◆ moon_orbit_at()

◆ node_period() [1/3]

◆ node_period() [2/3]

◆ node_period() [3/3]

◆ node_rate() [1/2]

◆ node_rate() [2/2]

◆ periapsis()

◆ period()

◆ pole() [1/4]

◆ pole() [2/4]

◆ pole() [3/4]

◆ pole() [4/4]

◆ position()

◆ reference_jd_tdb()

◆ reference_mean_anomaly()

◆ semi_major_axis()

◆ system()

◆ to_string()

◆ velocity()