SpiceState.position_light_time

giant.utilities.spice_interface:

SpiceState.position_light_time(date)

Make the call to spkezr given the stored settings at the input date returning both the state vector in kilometers and kilometers per second and the light time in TDB seconds.

Specifically the call is

spiceypy.spkezr(self.target, datetime_to_et(date), self.reference_frame, self.corrections, self.observer)

where datetime_to_et() converts a datetime object into ephemeris (TDB) seconds since the J2000 epoch.

Parameters:

date (datetime) – The date we are querying spice at as a datetime object

Returns:

The relative state vector in kilometers and kilometers per second and the one way light time between the observer and the target in TDB seconds as a tuple.

Return type:

Tuple[ndarray, float]