RA

class astropy.coordinates.angles.RA(angle, unit=None) [edit on github][source]

Bases: astropy.coordinates.angles.Angle

An object that represents a right ascension angle.

This object can be created from a numeric value along with a unit. If the value specified is greater than “24”, then a unit of degrees is assumed. Bounds are fixed to [0,360] degrees.

Parameters :

angle : float, int, str, tuple

The angle value. If a tuple, will be interpreted as (h, m s) or (d, m, s) depending on unit. If a string, it will be interpreted following the rules described above.

unit : UnitBase, str

The unit of the value specified for the angle. This may be any string that Unit understands, but it is better to give an actual unit object. Must be one of degree, radian, or hour.

Raises :

`~astropy.coordinates.errors.UnitsError` :

If a unit is not provided or it is not hour, radian, or degree.

Methods Summary

hour_angle(lst) Computes the hour angle for this RA given a local sidereal time (LST).
lst(hour_angle) Calculates the local sidereal time (LST) if this RA is at a particular hour angle.

Methods Documentation

hour_angle(lst) [edit on github][source]

Computes the hour angle for this RA given a local sidereal time (LST).

Parameters :

lst : Angle, Time

A local sidereal time (LST).

Returns :

hour_angle : Angle

The hour angle for this RA at the LST lst.

lst(hour_angle) [edit on github][source]

Calculates the local sidereal time (LST) if this RA is at a particular hour angle.

Parameters :

hour_angle : Angle

An hour angle.

Returns :

lst : Angle

The local siderial time as an angle.

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