  Assuming that the spin $a$ of the black hole, presumably located at the core
of the active galactic nuclei Messier 87 (M87), takes the value which maximises
the ergospheric volume of the Kerr spacetime, we find results compatible with
the recent observations obtained by high resolution interferometry on the
origin of the jet, which would be located inside the innermost stable circular
orbit diameter. Moreover, we find a flow of unbound geodesics issued from the
ergoregion able to frame the best fits at large scale recently obtained for
describing the observed profile of the relativistic jet launched from this
central engine.
