def _propagate_ecef(self, when_utc=None):
"""Return position and velocity in the given date using ECEF coordinate system."""
position_eci, velocity_eci = self._propagate_eci(when_utc)
gmst = gstime_from_datetime(when_utc)
position_ecef = coordinate_systems.eci_to_ecef(position_eci, gmst)
velocity_ecef = coordinate_systems.eci_to_ecef(velocity_eci, gmst)
return position_ecef, velocity_ecef
def _propagate_ecef(self, when_utc):
"""Return position and velocity in the given date using ECEF coordinate system."""
timetuple = (when_utc.year, when_utc.month, when_utc.day,
when_utc.hour, when_utc.minute, when_utc.second)
position_eci, velocity_eci = self.propagator.propagate(*timetuple)
gmst = _gstime(jday(*timetuple))
position_ecef = coordinate_systems.eci_to_ecef(position_eci, gmst)
velocity_ecef = coordinate_systems.eci_to_ecef(velocity_eci, gmst)
return (position_ecef, velocity_ecef)
def _propagate_only_position_ecef(self, when_utc):
"""Return position in the given date using ECEF coordinate system."""
jd, fr = jday_from_datetime(when_utc)
status, position_eci, _ = self._propagator.sgp4(jd, fr)
if status != 0:
raise PropagationError(SGP4_ERRORS[status])
gmst = gstime(jd + fr)
return coordinate_systems.eci_to_ecef(position_eci, gmst)
def get_only_position_jd(self, jd: float) -> np.ndarray:
"""
Get satellite position in ECEF coordinates [km]
"""
status, position_eci, _ = self._propagator.sgp4(jd, 0.0)
if status != 0:
raise PropagationError(SGP4_ERRORS[status])
gmst = gstime(jd)
pos_tuple = eci_to_ecef(position_eci, gmst)
return np.array(pos_tuple)
def _propagate_only_position_ecef(self, timetuple):
"""Return position in the given date using ECEF coordinate system."""
position_eci, _ = self.propagator.propagate(*timetuple)
gmst = _gstime(jday(*timetuple))
return coordinate_systems.eci_to_ecef(position_eci, gmst)