BarycentricTrueEcliptic

class astropy.coordinates.BarycentricTrueEcliptic(*args, copy=True, representation_type=None, differential_type=None, **kwargs)

Bases: BaseEclipticFrame

Barycentric true ecliptic coordinates. These origin of the coordinates are the barycenter of the solar system, with the x axis pointing in the direction of the true (not mean) equinox as at the time specified by the equinox attribute (as seen from Earth), and the xy-plane in the plane of the ecliptic for that date.

The frame attributes are listed under Other Parameters.

Parameters:

dataBaseRepresentation subclass instance

A representation object or None to have no data (or use the coordinate component arguments, see below).

lonAngle, optional, keyword-only

The ecliptic longitude for this object (lat must also be given and representation must be None).

latAngle, optional, keyword-only

The ecliptic latitude for this object (lon must also be given and representation must be None).

distanceQuantity [:ref: ‘length’], optional, keyword-only

The distance for this object from the barycenter. (representation must be None).

pm_lon_coslatQuantity [‘angualar speed’], optional, keyword-only

The proper motion in the ecliptic longitude (including the cos(lat) factor) for this object (pm_lat must also be given).

pm_latQuantity [:ref: ‘angular speed’], optional, keyword-only

The proper motion in the ecliptic latitude for this object (pm_lon_coslat must also be given).

radial_velocityQuantity [:ref: ‘speed’], optional, keyword-only

The radial velocity of this object.

representation_typeBaseRepresentation subclass, python:str, optional

A representation class or string name of a representation class. This sets the expected input representation class, thereby changing the expected keyword arguments for the data passed in. For example, passing representation_type='cartesian' will make the classes expect position data with cartesian names, i.e. x, y, z in most cases unless overridden via frame_specific_representation_info. To see this frame’s names, check out <this frame>().representation_info.

differential_typeBaseDifferential subclass, python:str, python:dict, optional

A differential class or dictionary of differential classes (currently only a velocity differential with key ‘s’ is supported). This sets the expected input differential class, thereby changing the expected keyword arguments of the data passed in. For example, passing differential_type='cartesian' will make the classes expect velocity data with the argument names v_x, v_y, v_z unless overridden via frame_specific_representation_info. To see this frame’s names, check out <this frame>().representation_info.

copybool, optional

If True (default), make copies of the input coordinate arrays. Can only be passed in as a keyword argument.

Other Parameters:

equinoxTime, optional

The date to assume for this frame. Determines the location of the x-axis and the location of the Earth and Sun. Defaults to the ‘J2000’ equinox.

Attributes Summary

default_differential	Default representation for differential data (e.g., velocity)
default_representation	Default representation for position data
equinox
frame_attributes
frame_specific_representation_info	Mapping for frame-specific component names
name

Attributes Documentation

default_differential

Default representation for differential data (e.g., velocity)

default_representation

Default representation for position data

equinox = <Time object: scale='tt' format='jyear_str' value=J2000.000>

frame_attributes = {'equinox': <astropy.coordinates.attributes.TimeAttribute object>}

frame_specific_representation_info

Mapping for frame-specific component names

name = 'barycentrictrueecliptic'