radeczn

ssapy.correlate_tracks.radeczn(orbit, arc, **kw)[source][source]

Computes right ascension, declination, range, proper motions, range rate, and mean anomaly wrap for a given orbit and observation arc.

Parameters:

orbitobject or list of objects

Orbital object(s) containing orbital parameters. Must include: - meanMotion: Mean motion of the orbit (scalar or array-like). - t: Epoch time of the orbit. - r (optional): Orbital position vector (used to determine scalar or array-like orbit).

arcstructured array

Observation arc containing time and station data. Must include: - ‘time’: Observation times (assumed to have a .gps attribute). - ‘rStation_GCRF’: Position of the station in the GCRF frame (in meters). - ‘vStation_GCRF’: Velocity of the station in the GCRF frame (in meters per second). - ‘satID’ (optional): Satellite IDs (used to determine scalar or array-like arc).

**kwdict, optional

Additional keyword arguments to pass to the ssapy.compute.radec function.

Returns:

tuple

A tuple containing the following computed values: - rr : ndarray

Right ascension values (in radians).

  • ddndarray

    Declination values (in radians).

  • zzndarray

    Range values (distance from observer to object, in meters).

  • pmrrndarray

    Proper motion in right ascension (in radians per second).

  • pmddndarray

    Proper motion in declination (in radians per second).

  • dzzdtndarray

    Range rate (rate of change of range, in meters per second).

  • nwrapndarray

    Mean anomaly wrap values, computed as meanMotion * (arc[‘time’].gps - orbit.t).