Transforming between equatorial systems

Expressing coordinates in the equatorial coordinate systems of choice, such as ICRS/GCRS, J2000, B1950, Mean of Date (MOD), True-of-Date (TOD), or CIRS of date. More...

Classes
class	supernovas::Equatorial
	Equatorial coordinates (RA, Dec = α, δ), representing the direction ob the sky, for a particular type of equatorial coordinate reference system, relative to the equator and equinox on that system. More...

Functions
Equatorial	supernovas::AstrometricPosition::as_equatorial () const
	Returns the equatorial coordinates place of this position, as would be seen by a stationary (w.r.t.
Equatorial	supernovas::Apparent::cirs () const
	Returns the apparent equatorial coordinates on the sky, in the Celestial Intermediate Reference System (CIRS).
Equatorial	supernovas::Apparent::equatorial () const
	Returns the apparent equatorial coordinates on the sky, with respect to the true equator and equinox of date (True-of-Date; TOD).
Equatorial	supernovas::Geometric::equatorial () const
	Returns the geometric equatorial coordinates, in the system in which the geometric positions and velocities were defined.
Equatorial	supernovas::Ecliptic::to_equatorial () const
	Returns a reference to a statically defined standard invalid Galactic coordinates.
Equatorial	supernovas::Galactic::to_equatorial () const
	Converts these galactic coordinates to equivalent ICRS equatorial coordinates.
Equatorial	supernovas::Equatorial::to_icrs () const
	Converts these equatorial coordinates to the International Celestial Reference System (ICRS).
Equatorial	supernovas::Equatorial::to_system (const Equinox &system) const
	Converts these equatorial coordinates to another equatorial coordinate system.

Detailed Description

Expressing coordinates in the equatorial coordinate systems of choice, such as ICRS/GCRS, J2000, B1950, Mean of Date (MOD), True-of-Date (TOD), or CIRS of date.

Function Documentation

as_equatorial()

Equatorial supernovas::AstrometricPosition::as_equatorial

(

)

const

Returns the equatorial coordinates place of this position, as would be seen by a stationary (w.r.t.

the SSB) observer located at the reference place.

Returns

the nominal equatorial place of this position, in the reference system in which this position was defined, at the time it is observed at the reference position in the solar-system. It does not contain aberration corrections for a moving observer, nor gravitational deflection around the major Solar-system bodies. Both of those are included in Apparent places instead.

See also

Apparent::equatorial()

References supernovas::Vector::_array(), supernovas::Unit::deg, supernovas::Equinox::from_system_type(), supernovas::Unit::hour_angle, supernovas::Validating::is_valid(), obs_time(), and vector2radec().

cirs()

Equatorial supernovas::Apparent::cirs

(

)

const

Returns the apparent equatorial coordinates on the sky, in the Celestial Intermediate Reference System (CIRS).

CIRS is defined on the true equator of date, but its origin is the Celestial Intermediate Origin (CIO), not the true equinox of date.

Returns

the CIRS equatorial coordinates in the observing frame.

See also

equatorial(), ecliptic(), galactic(), to_horizontal()

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

Referenced by cirs().

equatorial() [1/2]

Equatorial supernovas::Apparent::equatorial

(

)

const

Returns the apparent equatorial coordinates on the sky, with respect to the true equator and equinox of date (True-of-Date; TOD).

Returns

True-of-date (TOD) equatorial coordinates in the observing frame.

See also

cirs(), ecliptic(), galactic(), to_horizontal()

References supernovas::Unit::deg, equatorial(), supernovas::Unit::hour_angle, supernovas::Validating::is_valid(), and supernovas::Equinox::tod().

Referenced by ecliptic(), equatorial(), galactic(), and to_string().

equatorial() [2/2]

Equatorial supernovas::Geometric::equatorial

(

)

const

Returns the geometric equatorial coordinates, in the system in which the geometric positions and velocities were defined.

Note, that these coordinates are phyisical, and not what an observer would perceive at the time of observation, because:

• they are not corrected for aberration for a moving observer.
• they do not account for gravitational bending around massive Solar-system bodies, as light travels to the observer.

If you are interested in observable equatorial coordinates, see Apparent::equatorial() instead.

Returns

geometric equatorial coordinates.

See also

Apparent::equatorial(), ecliptic(), galactic(), position(), velocity()

References supernovas::Equinox::from_system_type(), and supernovas::Validating::is_valid().

Referenced by ecliptic(), and galactic().

to_equatorial() [1/2]

Equatorial supernovas::Ecliptic::to_equatorial

(

)

const

Returns a reference to a statically defined standard invalid Galactic coordinates.

These invalid coordinates may be used inside any object that is invalid itself.

Returns

a reference to the static standard invalid coordinates. Converts these ecliptic coordinates to equivalent equatorial coordinates

the equivalent equatorial coordinates for the same place on sky.

See also

Equatorial::to_ecliptic(), to_galactic()

References supernovas::Unit::deg, ecl2equ(), supernovas::Unit::hour_angle, supernovas::Validating::is_valid(), supernovas::Spherical::latitude(), supernovas::Spherical::longitude(), NOVAS_FULL_ACCURACY, system(), and supernovas::Equatorial::undefined().

Referenced by to_galactic(), to_icrs(), to_j2000(), to_mod(), to_system(), and to_tod().

to_equatorial() [2/2]

Equatorial supernovas::Galactic::to_equatorial

(

)

const

Converts these galactic coordinates to equivalent ICRS equatorial coordinates.

Returns

the equivalent ICRS equatorial coordinates.

See also

Equatorial::to_galactic(), to_ecliptic()

References supernovas::Unit::deg, gal2equ(), supernovas::Unit::hour_angle, supernovas::Equinox::icrs(), supernovas::Validating::is_valid(), supernovas::Spherical::latitude(), supernovas::Spherical::longitude(), and supernovas::Equatorial::undefined().

Referenced by to_ecliptic().

to_icrs()

Equatorial supernovas::Equatorial::to_icrs

(

)

const

Converts these equatorial coordinates to the International Celestial Reference System (ICRS).

Returns

new equatorial coordinates, which represent the same equatorial position as this, but expressed in the ICRS (= FK6).

See also

to_system()

References supernovas::Equinox::icrs(), supernovas::Validating::is_valid(), and to_system().

Referenced by to_galactic(), and supernovas::Ecliptic::to_icrs().

to_system()

Equatorial supernovas::Equatorial::to_system

(

const Equinox &

system

)

const

Converts these equatorial coordinates to another equatorial coordinate system.

Parameters

system

the equatorial coordinate system (type and epoch) to convert to.

Returns

new equatorial coordinates, which represent the same equatorial position as this, but expressed in the specified other coordinate reference system.

See also

operator>>(), to_icrs(), to_j2000(), to_hip(), to_mod(), to_mod_at_besselian_epoch(), to_tod(), to_cirs()

References cirs_to_gcrs(), dec(), supernovas::Unit::deg, gcrs_to_cirs(), gcrs_to_j2000(), gcrs_to_mod(), gcrs_to_tod(), supernovas::Unit::hour_angle, supernovas::Validating::is_valid(), j2000_to_gcrs(), mod_to_gcrs(), NOVAS_CIRS, NOVAS_FULL_ACCURACY, NOVAS_GCRS, NOVAS_ICRS, NOVAS_J2000, NOVAS_MOD, NOVAS_TOD, ra(), radec2vector(), system(), tod_to_gcrs(), undefined(), and vector2radec().

Referenced by operator>>(), to_cirs(), to_hip(), to_icrs(), to_j2000(), to_mod(), to_mod_at_besselian_epoch(), supernovas::Ecliptic::to_system(), and to_tod().