Must there be an accretion disc for astrophysical jet to form? Does it have anything to do with how massive the star is? Since it is already a hot plasma and produce it's own magnetic field, can't it accelerate ions from the axis of rotation? If the accretion disc is far away as in M87 then how did it ends up at the poles? I just read Event Horizon Telescope project were detecting 230Ghz or 1.3mm wavelength of light, any higher frequency will improve the resolution of the image but I'm wondering is it possible to trace the magnetic line if we get much clearer picture? Although there are many questions here but they are very much the same thing asking about the source of astrophysical jet.