dsgp4.newton_method

dsgp4.newton_method(tle_0, time_mjd, target_state=None, new_tol=1e-12, max_iter=50)

This method performs Newton method starting from an initial TLE and a given propagation time. The objective is to find a TLE that accurately reconstructs the propagated state, at observation time.

Parameters:

tle_0 (dsgp4.tle.TLE): starting TLE (i.e., TLE at a given initial time) time_mjd (float): time at which we want to propagate the TLE (in Modified Julian Date) target_state (torch.tensor): a 2x3 tensor for the position and velocity of the state. If None, then this is computed by propagating tle_0 at the new_date. new_tol (float): tolerance for the Newton method max_iter (int): maximum number of iterations for the Newton method

Returns:

next_tle (dsgp4.tle.TLE): TLE corresponding to the propagated state y0 (torch.tensor): initial guess for the TLE elements. In particular, y0 contains the following elements (see SGP4 for a thorough description of these parameters):