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- Astropy v5.2.1 »
- Astronomical Coordinate Systems (`astropy.coordinates`) »
- get_body_barycentric

# get_body_barycentric

astropy.coordinates.get_body_barycentric(body, time, ephemeris=None)

  Calculate the barycentric position of a solar system body.

  Parameters:
    body `python:str` or `python:list` of `python:tuple`

      The solar system body for which to calculate positions. Can also be a kernel specifier (list of 2-tuples) if the `ephemeris` is a JPL kernel.

    time `Time`

      Time of observation.

    ephemeris `python:str`, optional

      Ephemeris to use. By default, use the one set with `astropy.coordinates.solar_system_ephemeris.set`

  Returns:
    position `CartesianRepresentation`

      Barycentric (ICRS) position of the body in cartesian coordinates

  See also

  `get_body_barycentric_posvel`

    to calculate both position and velocity.

  Notes

  You can either give an explicit ephemeris or use a default, which is normally a built-in ephemeris that does not require ephemeris files. To change the default to be the JPL ephemeris:

      >>> from astropy.coordinates import solar_system_ephemeris
      >>> solar_system_ephemeris.set('jpl')

  Use of any JPL ephemeris requires the jplephem package (https://pypi.org/project/jplephem/). If needed, the ephemeris file will be downloaded (and cached).

  One can check which bodies are covered by a given ephemeris using:

      >>> solar_system_ephemeris.bodies
      ('earth', 'sun', 'moon', 'mercury', 'venus', 'earth-moon-barycenter', 'mars', 'jupiter', 'saturn', 'uranus', 'neptune')