def galactic(obj=None, frame=None, tstart=None, tend=None, tstep=None, time=None, mode=None):
if mode is None:
raise AssertionError('Must specify mode: either center times (c) or boundary times (b).')
if time is not None and (tstart is not None or tend is not None or tstep is not None):
raise AssertionError('Must enter one time, or a start time, end time, and time step')
elif time is not None:
with solar_system_ephemeris.set('jpl'):
jup = get_body(obj, date)
ra = jup.ra.value
dec = jup.dec.value
time = jup.obstime.value
jup_ephem = SkyCoord(ra, dec, frame=frame, unit='deg', obstime=time)
elif time is None and (tstart is None or tend is None or tstep is None):
raise AssertionError('Must enter start time, end time, and time step')
elif time is None and (tstart is not None and tend is not None and tstep is not None):
if mode == 'c':
tstart = tstart.mjd + (tstep/2) #use this line if you want times in the center of timeranges, dont use if you want coordinates at the time intervals themselves
elif mode == 'b':
tstart= tstart.mjd # use if you want coordinates at time intervals not at center of intervals
tend = tend.mjd
times = np.arange(tstart, tend, tstep, dtype=float)
times_list = Time(times, format='mjd').fits
times_list = Time(times_list, format='fits')
jup_ephem = list()
for date in times_list:
with solar_system_ephemeris.set('jpl'):
jup = get_body(obj, date)
ra = jup.ra.value
dec = jup.dec.value
time = jup.obstime.value
jup2 = SkyCoord(ra, dec, frame=frame, unit='deg', obstime=time)
jup_ephem.append(jup2.galactic)
return jup_ephem
