astro.Groundtrack

class hohmannpy.astro.Groundtrack(satellite, initial_gmst, solver_tol=1e-08)

The groundtrack of a Satellite projected onto an ellipsoidal Earth.

These are stored as geodetic latitude and longitude history arrays. Note that for this class to work, the satellite must already have had its orbit propagated via Propagator or one of its child classes. In addition, while the GMST of the Earth is initially computed accurately it is then assumed to evolve linear at the Earth’s mean rotation rate (ignoring nutation).

Parameters:

• satellite (Satellite) – Satellite whose orbit should be used to generate a groundtrack.

• initial_gmst (float) – GMST of the Earth at the satellite’s initial position.

• solver_tol (float) – Root-finding is used to compute the geodetic latitude of the satellite, this is the error tolerance.

Variables:

• latitude_history (np.ndarray) – The geodetic latitude of the satellite at each timestep stored in its time_history attribute.

• longitude_history (np.ndarray) – The longitude of the satellite at each timestep stored in its time_history attribute.