Jet (green) and counter-jet (blue) longitudinal intensity profile and their corresponding ratio (orange). The gray shading indicates the span travelled by the SSP detected on the counter-jet side for which the speed has been robustly estimated. In order to exclude biasing by the bright core of the jet, only measurements at core separations larger than 0.4 mas (≈1.4 FWHM of the restoring beam) are considered in the analysis of the jet/counter-jet ratio.