CeeBee ceebee@novalidmail wrote in
2.164:

" wrote in alt.astronomy:


What causes it to be forced away from the accretion disk, whereas the
rest of the matter is "sucked" towards it?

Outside the event horzion there are stable orbits possible, with matter
neither sucked in nor repelled away. Think of the Earth's orbit around
the Sun. Come too close, you end up sucked in, get too far too fast and
you'll never see the Sun again. Right speed and distance, and you'll
have a stable orbit.

It's not quite understood, but due to the fast rotation of the black
hole magnetic fields emerge, enabling matter in the accretion disk,
outside the event horzion, spinning around the black hole to be
jettisoned away.

In this model the magnetic fields are intertwined and create channels
that might conduct the jets.

A nice introduction to black holes:

http://hubblesite.org/discoveries/black_holes/


I recall reading somewhere that black holes act as extremely efficient
"power stations" in this process. The kinetic energy of the emitted jets is
a high proportion of the gravitational potential energy of the infalling
material. Having now solved the energy crisis we will now hand this over to
the engineering department to sort out the practical details ;-).

Klazmon.