cartesian_lsr

sofia_redux.spectroscopy.earthvelocity.cartesian_lsr(definition='kinematic')[source]

Find the radial LSR velocity towards sky coordinates.

The Local Standard of Rest allows for two different definitions:

  • ‘kinematic’ uses 20 km/s towards 18:00:00, +30:00:00 (‘J1900’)

  • ‘dynamical’ uses the IAU definition of 9, 12, and 7 km/s along the x, y, and z axis in Galactic cartesian coordinates.

Parameters:
definitionstr, optional

One of {‘kinematic’, ‘dynamical’}

Returns:
lsr_velCartesianRepresentation

Cartesian representation of the LSR velocity in km / s