HeliocentricEclipticIAU76#
- class astropy.coordinates.HeliocentricEclipticIAU76(*args, copy=True, representation_type=None, differential_type=None, **kwargs)[source]#
Bases:
BaseEclipticFrame
Heliocentric mean (IAU 1976) ecliptic coordinates. These origin of the coordinates are the center of the sun, with the x axis pointing in the direction of the mean (not true) equinox of J2000, and the xy-plane in the plane of the ecliptic of J2000 (according to the IAU 1976/1980 obliquity model). It has, therefore, a fixed equinox and an older obliquity value than the rest of the frames.
The frame attributes are listed under Other Parameters.
{params}
- Parameters:
- data
BaseRepresentation
subclass instance A representation object or
None
to have no data (or use the coordinate component arguments, see below).- lon
Angle
, optional, keyword-only The ecliptic longitude for this object (
lat
must also be given andrepresentation
must be None).- lat
Angle
, optional, keyword-only The ecliptic latitude for this object (
lon
must also be given andrepresentation
must be None).- distance
Quantity
[:ref: ‘length’], optional, keyword-only The distance for this object from the sun’s center. (
representation
must be None).- pm_lon_coslat
Quantity
[‘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_lat
Quantity
[:ref: ‘angular speed’], optional, keyword-only The proper motion in the ecliptic latitude for this object (
pm_lon_coslat
must also be given).- radial_velocity
Quantity
[:ref: ‘speed’], optional, keyword-only The radial velocity of this object.
- representation_type
BaseRepresentation
subclass,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 viaframe_specific_representation_info
. To see this frame’s names, check out<this frame>().representation_info
.- differential_type
BaseDifferential
subclass,str
,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 namesv_x, v_y, v_z
unless overridden viaframe_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.
- data
Attributes Summary
Default representation for differential data (e.g., velocity)
Default representation for position data
Mapping for frame-specific component names
The reference time (e.g., time of observation)
Attributes Documentation
- default_differential#
Default representation for differential data (e.g., velocity)
- default_representation#
Default representation for position data
- frame_attributes = {'obstime': <astropy.coordinates.attributes.TimeAttribute object>}#
- frame_specific_representation_info#
Mapping for frame-specific component names
- name = 'heliocentriceclipticiau76'#
- obstime#
The reference time (e.g., time of observation)
Default: J2000.000