A getter for the wavelength bin centers and average fluxes

def centers(self):
        """A getter for the wavelength bin centers and average fluxes"""
        # Get the bin centers
        w_cen = np.nanmean(self.wave.value, axis=1)
        f_cen = np.nanmean(self.throughput, axis=1)

        return np.asarray([w_cen, f_cen])