In reply to Bob Higgins's message of Sat, 2 Dec 2017 07:01:42 -0700:
>Hi Robin, Can you supply a link? The only thing I can find with ion
>thrusters is that the magnetic field is used to prevent the ions from
>striking the side walls. I didn't find anything that suggests that a
>magnetic field can turn high energy ion trajectories from an
>omnidirectional source into unidirectional thrust. Magnetic fields only
>make the ion path curl.
I'll see what I can dig up. IIRC, the field is more intense at the point of the
V and less at the other (open) end. The result is that charged particles
"bounce" where the field is intense, and escape at the other end, with a net
thrust applied to the rocket via the magnetic field.
You see a similar phenomenon with the charged particles in the Van Allen belts,
where they oscillate back and forth between the Earth's magnetic poles.
The jets (particle streams) emitted by some black holes may be another example.
Robin van Spaandonk
local asymmetry = temporary success