galpy.util.coords.pmllpmbb_to_pmrapmdec

galpy.util.coords.pmllpmbb_to_pmrapmdec(pmll, pmbb, l, b, degree=False, epoch=2000.0)[source]

NAME:

pmllpmbb_to_pmrapmdec

PURPOSE:

rotate proper motions in (l,b) into proper motions in (ra,dec)

INPUT:

pmll - proper motion in l (multiplied with cos(b)) [mas/yr]

pmbb - proper motion in b [mas/yr]

l - Galactic longitude

b - Galactic latitude

degree - if True, l and b are given in degrees (default=False)

epoch - epoch of ra,dec (right now only 2000.0 and 1950.0 are supported when not using astropy’s transformations internally; when internally using astropy’s coordinate transformations, epoch can be None for ICRS, ‘JXXXX’ for FK5, and ‘BXXXX’ for FK4)

OUTPUT:

(pmra x cos(dec),pmdec), for vector inputs [:,2]

HISTORY:

2010-04-07 - Written - Bovy (NYU)

2014-06-14 - Re-written w/ numpy functions for speed and w/ decorators for beauty - Bovy (IAS)