Where do the jets in active galactic nuclei come from?
We think that the accretion disk of gas and dust which orbits supermassive
black holes is pretty hot and messy. The inner regions are heated to thousands
of degrees by viscous forces, and trapped magnetic fields become buoyant and
pop out of the disk like solar prominences do. As the plasma is compressed
near the event horizon of the black hole ....about the diameter of our solar
system, the magnetic fields bulge outwards along the rotation axis of the disk
and act like electromagnetic pipes, down which plasma can be ejected and
accelerated to nearly the velocity of light just as we build linear
accelerators here on earth to do the same trick. Evidently, the plasma
is expelled in clouds called plasmons, just as solar prominences and flares
expel matter off of the surface of the sun from time to time.
The net result are jets of accelerated plasma which we can see with radio and
optical telescopes here on earth millions of light years away.
Copyright 1997 Dr. Sten Odenwald
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