circular_guess

ssapy.rvsampler.circular_guess(arc, indices=[0, 1])

Guess position and velocity from two closely spaced (in time) observations of ra/dec.

The state is inferred by finding the circular orbit passing through the two points, assuming the motion in between the observations is inertial.

Parameters:

• arc (QTable with columns for 'ra', 'dec', 'rStation_GCRF'.) – The set of observations used to make the guess. Note, only indices rows of the given QTable will be used.

• indices (list of indices indicating which two observations in arc to use) – for initialization. Default: [0, 1]; i.e., use the first two observations.

Returns:

state – state corresponding to orbit passing through points

Return type:

array_like, (6,)